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Introduction to Prolog Programming

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Why we need Prolog programming?

It is a first-order logic programming language.

The programmer does not require complex algorithms and coding.

this programming is easier for Pattern matching and searching data than in other programming languages.

It works with abstract models and deals with objects.

This programming is the prolog is an easy, simple, and formula-based programming language.

This programming separates logics and controls of the data.

The prologs are based on the symbolic and computation for manipulation.

It is based on numerical data for pattern matching.

This programming language is a relational database for maintaining a memory management system.

It provides small syntaxes and small coding patterns.

It is based on the searching tree of determination and possibility.

The prolog supports a lot of the extensions like socket interface, global variables, and operating system interfaces.

It supports the native code compiler and becomes a stand-alone programming language.

The prolog supports constraints like arithmetic, Boolean, symbolic, etc.

This programming provides an efficient constraint solver and makes compatibility with integrals and variables.

The prolog supports compiled predicates and consulted predicates in the compiler.

This programming supports powerful interfaces between the prolog and C programming language.

How does Prolog programming works?

The following shows the prologue programming’s working environment.

Download or save the software in the required path.

The downloaded software saves in the exe file format to install the software.

The working procedure of the prolog programming shows below.

The warren abstract machine (WAM) is working as a compiler for prolog language.

The compiler file is converted into independent low-level machine language.

The resulting file again translates into the target machine.

This working procedure makes a stand-alone programming language.

Advanced prolog programming requires constraints for problem-solving.

You choose arithmetic constraints, Boolean constraints, and symbolic constraints, and so on.

The basic procedure of this programming is shown below.

The prolog software creates a file with the chúng tôi format. The “*.pl” is an extension of the prolog file.

Write the syntax of the prolog programming language. You can use many entities in single relation.

It shows the basic syntax below.

Format –

relation (objects or data). relation (data1, data2, data).

The prolog programming example shows the basic output.




The Prolog programming software is easy to build and install the software.

This programming language does not need lengthy syntax and coding.

This compiler is working fast and hustle-free.

It has powerful interfaces between the prolog and C programming language.

The user of prolog programmer creates their constraints with customization.

The prolog programmer provides several extensions.

This programming language provides high-level and categorized constraints.

The prolog supports easier pattern matching and searching data features.

The prolog language does not use complex algorithms and coding.

This language maintains and operates data lists with easy coding.

The several algorithm and code for input and output procedures are not easy.

The LISP language dominates and overcomes input and output features.

It does not support graphics features. If you need graphics, then you must use turbo prolog.

The prolog order affects the efficiency of the programming language.

This language does not support the “OR” logical conditions. This language does not support multiple true statements.

This language does not support the “NOT” logical condition. This language does not support negative statements.

The prolog is first-order logic language. This language does not allow second-order logic directly.


It is mostly usable in artificial intelligence technology.

This programming language uses for pattern matching using the parse tree feature.

The prolog is used in the computation schematics.

This programming uses in the problem-solving and understanding of natural language.

This language uses planning and designing of the robot.

The prolog is used in the automation system and theorem proving with a variety of constraints.

The prolog is a useful language in machine learning and the graphical user interface.

This is used for expert system and term rewriting using arithmetic and symbolic constraints.


It is simple planning and problem-solving programming language.

This language is used for AI, machine learning, and computational technology.

The prolog works in large-size applications in small and easy coding.

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How Does Encryption Work?




A B C D E F G H I J K L M N O P Q R S T U V W X Y Z More alphabets and unbreakable encryption

The weaknesses of the Caesar substitution cipher can be slightly alleviated by using more than one shifted alphabet. The example below can be expanded to 26 shifted alphabets of which several are used at once, but not all of them.





Rather than doing a straight substitution this time we use addition, with a twist. Each letter of the alphabet is assigned a number, A is 0, B is 1, C is 2 and so on. I is the 9th letter of the alphabet, which means it has a value of 8. P (the letter below it on our one-time-cipher pad) 15. 8 + 15 = 25 which means X. The second letter of our message is S, which has the value 18. It just so happens that S is also the letter on our one-time pad (which isn’t an issue at all). 18 + 18 = 36. Now here is the twist, there is no 36th letter of the alphabet. So we perform what is called a modulus operation. What that basically means is that we divided the result by 26 (the number of letters in the alphabet) and use the remainder. 36 / 26 = 1 remainder 10. The letter with the value of 10 is K. If you continue doing this the final encrypted message is:

Computers are flexible, unlike mechanical boxes, computers can be programmed to perform lots of different operations on a message and the number and complexity of these operations can be altered relatively quickly.


Computers deal with binary numbers not just letters.

Exclusive OR (XOR) – This is a bit level logical operation that is applied to 2 input bits A and B. The Exclusive OR returns true or false (1 or 0) to the question, “A or B, but not, A and B”. You can think of it as, “one or the other but not both”. So, if A is 1 and B is 0 then that is one or the other, so the result is 1 (true). The same result applies to A is 0 and B is 1. But if A is 0 and B is 0 then the result is 0 (false), as both have the same value. False is also given for A is 1 and B is 1.

But the real magic of XOR is that it is reversible. If A XOR B = C then B XOR C = A, and A XOR C = B. This is very important for encryption as it means that data can be encrypted (where A is the data) using a key (B) to get the encrypted data (C). Later the encrypted data can be decrypted by XOR it with the key again to get the original data. The reason XOR is used in conjunction with complicated round functions and bit shifting operations is because on its own XOR can be broken using frequency analysis (because of the constantly repeating key).

Public key cryptography and wrap-up

How Does Wireless Charging Work?

Wireless charging lets you charge up your gadgets without having to plug in a USB cable. It’s pretty neat, but how does it actually work? Why even bother? What are the downsides? 

We’ll tackle everything you need to know about how wireless charging works right here. Soon you’ll forget what all that wire clutter was like!

Table of Contents

A Matter Of Induction, My Dear Watt(son)

Generally, wireless chargers use a property of magnetism and electricity known as “induction” charging. Basically, electric current is converted into a magnetic field. This field then induces an electric current in the device you want to charge.

That’s a bit of an oversimplification, but it’s essentially what happens in the wireless charging process. There are two coils, one in each device, that convert the energy from one form to another.

This is the most common form of wireless charging you’re likely to find in personal gadgets such as smartphones or smart watches. Induction charging only works over very short distances. Usually 10mm or less. So although the power is “wireless” you usually need to set the device down on some sort of charging pad for the power to flow. Induction chargers such as these use low frequency signals to move power from the charger to the device.

The Resonant Alternative

It’s a futuristic idea, but electrical pioneer Nikola Tesla was doing it more than a century ago. Had history gone in a slightly different direction, wireless electricity might have been the standard way of doing things today.

A Two-Horse Race

There are different approaches to how wireless charging works, each with their own pros and cons. Different companies have different visions as to how we all want to use wireless power in daily life. This has given rise to multiple standards for wireless charging and, as you’ve probably guessed, these standards don’t inter-operate.

Qi wireless chargers use the short-range induction method and this is what you’ll find in most personal devices that charge wirelessly.

The AirFuel standard uses the long-range resonant method and you’re not likely to find it built into your gadgets quite yet. However, you can buy special charging cases for smartphones that add AirFuel capability to them.

Faster! Faster!

One thing you may notice about wireless charging, regardless of the standard, is that they don’t offer that much power. Fast-charging has become pretty much the standard when using a cable. Modern USB-C smartphones and laptops can often accept anything between 40 and 60 watts. Using USB-C Power Delivery, you can actually move 100W of power over a USB-C cable, but not current lithium ion batteries in a phone can accept that.

Qi or AirFuel chargers don’t offer nearly as much power, but both standards are evolving. At the time of writing, 40W wireless fast charging has started to enter the market and AirFuel hopes to reach 100W at some point in the future. We can also expect battery technology to improve, making it easier to charge devices more quickly. 

However, as of right now, one major downside of wireless charging is that it’s slower than using a direct wire connection and it can’t actively power devices that need even a moderate amount of power to work.

One Charger To Rule Them All

So anyone with a Qi device can simply put it on your pad and charge up. That’s cool, but the real killer feature is the ability to charge multiple devices on the same charging pad at the same time. You need a charger with one coil for each device you want to charge. 

For example, “triple chargers” have three coils and therefore three charging spots. You can put three devices next to each other and have them charge at the same time. That can be a pretty elegant solution. For example, if you place a triple charger on a side table in your living room, it’s a central place where people can put their devices.

Devices That Only Charge Wirelessly

Most devices that charge wirelessly, such as smartphones, also give you the option of wired charging. However, there are some devices that only let you charge them wirelessly. Smartwatches are one example of this and when you think about it, it makes sense. 

If you want to create a device that’s truly dust and waterproof, having a bunch of ports can be a pain. Not to mention that small devices such as wireless buds or smartwatches often don’t have space for standard connectors anyway. 

How does wireless charging work on larger devices? While there are as yet no phones, tablets or laptops that we are aware of with exclusive wireless charging don’t assume it will never happen. A completely sealed device that uses only wireless communication and charging would open up new doors when it comes to ruggedization and design.

Phones & Power Banks That Provide Wireless Charging

Wireless chargers themselves have gone wireless in the sense that you can now get power banks and even smartphones that can charge devices wirelessly using the Qi standard. 

Smartphones such as the Note 10+ have a feature known as “Wireless Powershare” and it’s very handy for charging devices such as wireless earbuds or smartwatches. Wireless power banks are of course also useful for that use case, but it also brings up the interesting possibility of sticking your phone to the power bank and temporarily using it as one cable-free hunk.

A Wireless Future

Short-range Qi induction charging is certainly here to stay, but we’ve seen some impressive demonstrations of long range charging using the resonance method. Fitting an LCD TV with a receiver coil, simply bringing it within range of another coil installed within a wall will power it on. 

With both power and data transfer possible wirelessly, there are new avenues product designers can take. We might be heading for an interesting future of devices that always have power, don’t need to be opened and in some cases may no longer need batteries to operate.

Of course, it will be some time until long range wireless power becomes the norm. You can certainly expect quite a bit of pushback as well. There’s already plenty of (usually unwarranted) concerns about electromagnetic radiation technologies such as 5G causing health issues or environmental problems. We expect the same sorts of complaints to arise when long-range wireless power transmission becomes more common. 

How Iife Work In Javascript With Programming Examples

Introduction to JavaScript IIFE

The JavaScript Immediately Invoked Function Expression (IIFE) is a function which helps in providing a method that defines a sequence of a particular context. Once a variable is defined inside a function it is not possible to access it outside the function where it is defined. The functions which are created in JavaScript have named functions, anonymous functions and by making use of IIFE we can execute these as soon as they are mounted. This functionality makes them IIFE. Let us have a look in detail at how this function works

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Below is the syntax for JavaScript IIFE:

(function () { })();

Explanation: The primary use of this function is that the variables should be accessible only within the scope of the defined function that is there.

The declaration should begin with the keyword function(). In the function definition, you can define any statements which are to be performed. This function should be hoisted. A hoisted function is always placed at the start of the program or functional scope when the JavaScript code is being executed. You can also use the below syntax:

The parentheses let JavaScript know that there is a function expression and the last pair of parentheses will invoke the function.

How does IIFE work in JavaScript?

Let us see how does it work:


(function () { var userName = "Snehal"; function display(name) { alert("MyCode2.js: " + name); } display(userName); })();

The above code is an example of IIFE. The IIFE helps in including all functions and variables with the same name and they can be accessed globally. Here we define a function and in its definition,  we are creating a variable username. We immediately write another function that will display this username. This is the display function where we are sending the username as a parameter. We have created an alert for the same where we display the code script name and then by making use of IIFE we have simply called the function at the end. In this way we have called two functions one after the other. We have rather immediately invoked. Let us check a few examples to understand better.

Examples to Implement JavaScript IIFE

Below are the examples mentioned:

Example #1


// anonymous function #1 var isLucky = function() { var iife = Math.round(Math.random() * 100); return “You are checking Immediate Invoking Function Expression!”; } else { return “We are not in IIFE, better luck next time!”; } }; var me = isLucky(); alert(me); window.setTimeout(function() { alert(“JavaScript and EduCBA is awesome!!!”); }, 2000);

At first, the result is displayed as per the condition. When we again run the program the result is the else part. Once the time outspan is over then the output of the above program will be as below:

Explanation: The above script helps us understand the IIFE in Javascript better. Here we have created a function isLucky where we are rounding off a random number and then multiplying it by 100. The random number is being generated by the Math.random() function. After this number is generated then we check if the number is less or greater than 50. If the number is greater than 50 then the message will be displayed as: “You are checking Immediate Invoking Function Expression!”. Else the corresponding message for it will be displayed. Once this function is done we are calling it and storing it in a variable called me. Whatever message is returned it will be displayed in the form is an alert window in the browser. Just after this, another function is invoked. This function will time out and display another alert will be displayed. Below will be the output when we run for the first time.

Example #2

Let us take another example of IIFE. We can use this function without if else block as well.

(function() { var create = “I have learnt what is Immediate Invoking Function Expression from EduCBA successfully !!!”; alert(create); })(); window.setTimeout(function() { alert(“JavaScript and Edu is awesome!!!”); }, 2000);


The message is displayed as soon as the above code is run. Once the timeout happens below alert window turns up automatically.

Explanation: The above code is an example of a classic and simple IIFE. We create a function and immediately call it. We have not named this function with any name. We have just created a variable create. This function then uses this to display this message as the sun as the function is invoked. As per the syntax, we are bound to use the parenthesis correctly. If there are any misses in the parenthesis then the code will not give the desired result. We can easily invoke the function as soon as the function is declared and defined. We will just pass empty parentheses in order to invoke the function that we have created. We send the variable to create as a parameter to an alert. When the program is run the alert will be called and whatever is present in the created variable will be displayed in the alert window. We also created a similar function as in Example 1. This will work in a similar way. It will wait for timeout and will again display an alert window with the specified message. The timeout time we have mentioned here is 2 milliseconds. Once this is over the message will be displayed automatically. Let us see the output of the above code.


The Immediate Invoking Function Expression is an easy way of calling a function just after it is created. It helps in keeping the local variables local or global variables as global whenever required. It is fast and hence very efficient to use. It fulfills the programmer’s purpose of keeping the variables intact. IIFE can be used with a name or without any name. They can also be used with unary operators when needed.

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How Does Alias Work In Postgresql?

Introduction to PostgreSQL Alias

In simple terms, ALIAS means temporarily giving another name to a table or a column. To give the temporary name for tables or columns, we generally use PostgreSQL Alias. The PostgreSQL Aliases are used to create a temporary column or table name. The existence of aliasing is limited to the PostgreSQL statement’s execution means the PostgreSQL aliases are used to rename a column or a table in a specific PostgreSQL query. Hence the actual table name or column name does not change in the database. We generally use the temporary names while performing self join on the table to create a temporary table.

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We can use PostgreSQL Aliases to create a temporary name for columns, tables, or expressions. Let’s understand the syntax of Alias as below :

SELECT column [AS] alias_name FROM table;

2. PostgreSQL Aliases for expression

SELECT expression [AS] alias_name FROM table;

3. PostgreSQL Aliases for table

SELECT column FROM table [AS] alias_name;


Column: The actual column name to which we want to specify an alias.

table_name: The actual table name to which we want to specify an alias.

expression: An expression to which we want to specify an alias.

AS: It is the Optional keyword. AS keyword will not affect the Alias in the PostgreSQL statement, even if it is defined or not. In PostgreSQL, defining AS keyword or not is a programmer’s choice.

alias_name: The temporary name for expressions, columns, or tables. The PostgreSQL Alias name can have spaces. But it is not a best practice to have an alias name with spaces in case of aliasing a table.

How does Alias Work in PostgreSQL?

The PostgreSQL Aliases are used to remove the ambiguity for self-joins. The self join means the same table is getting scanned multiple times to retrieve the data. The PostgreSQL Alias is used with the optional ‘alias’ keyword, but if provided, it hides the actual name of the columns or tables. If we have specified the Alias in the PostgreSQL statement, we need to define the column names, and the Alias defined, and its scope is limited to the same statement only.


Consider a statement ‘FROM MyTable AS MT’, which we are using with a SELECT statement; then it uses the ‘MT’ and not the ‘MyTable’.

Consider the following statements to understand how PostgreSQL works for long table names:

SELECT long_table_name.column FROM long_table_name;

We can use the Alias for the long table name as follows:

SELECT ltn.column FROM long_table_name ltn;

Here we have specified the alias ‘ltn’ for a table ‘long_table_name’.

Examples to Implement Alias in PostgreSQL

Let’s create a table of name ‘student’ and ‘teacher’ to understand the PostgreSQL alias examples in detail:

Example #1

Create a table of name ‘student.’


CREATE TABLE student( rollno int PRIMARY KEY, firstname VARCHAR (50) NOT NULL, lastname VARCHAR (50) NOT NULL, branch VARCHAR (50) NOT NULL, result boolean, joining_date DATE NOT NULL );

Now, insert some data into thestudent’ table.

INSERT INTO student (rollno, firstname, lastname, branch, result, joining_date) values ('101', 'Oliver','Jake', 'Civil', false, '06-01-2024'), ('102', 'Jack','Connor', 'Computer', false, '06-01-2024'), ('103', 'Harry','Callum', 'Civil', false, '06-01-2024'), ('104', 'Jacob','John', 'Computer', false, '06-01-2024'), ('105', 'Thomas','David', 'Civil', false, '06-01-2024');

Now, illustrate the data inserted into the ‘student’ table with the following SQL statement’s help.

select * from student;

Example #2

Create a table of name ‘teacher.’


CREATE TABLE teacher ( teacher_id INT NOT NULL PRIMARY KEY, firstname VARCHAR (50) NOT NULL, lastname VARCHAR (50) NOT NULL, branch VARCHAR (50) NOT null, salary numeric ); INSERT INTO teacher (teacher_id, firstname, lastname, branch,salary) values ('1', 'Hugo','Smith', 'Computer',20000), ('2', 'Brayden','Johnson', 'Computer',30000), ('3', 'Ronan','Williams', 'Civil',35000), ('4', 'Antonio','Brown', 'Civil',40000), ('5', 'Marco','Davis', 'Civil',25000);

Now, illustrate the data inserted into the ‘teacher’ table with the following SQL statement’s help.

select * from teacher;

1. PostgreSQL Aliases for column

We specify the alias names to make the column headers more readable in the final result set. Like whenever we use functions like MAX, we can alias the result of the MAX function to make it easier to read.

SELECT firstname, MAX(salary) AS high_salary FROM teacher GROUP BY firstname;

Illustrate the result of the above statement using the following snapshot.

In the above example, we aliased MAX(salary) as ‘high_salary’. Therefore, the column header of the second column will be displayed as ‘high_salary’. In this example, we have not added any space in, so it does not need to add quotes around the given alias_name.

It is acceptable to add quotes around the alias_name in PostgreSQL Alias as follows:

SELECT firstname, MAX(salary) AS "high_salary" FROM teacher GROUP BY firstname;

Illustrate the result of the above statement using the following snapshot.

SELECT firstname, MAX(salary) AS "high salary" FROM teacher GROUP BY firstname;

Illustrate the result of the above statement using the following snapshot.

2. PostgreSQL Aliases for table

We generally use the Alias on the table if we want to abbreviate the name to the table to make the queries more readable and shorter, or in the case of SELF JOIN, where we use the same table multiple times. It is acceptable to define aliases for the tables you want to give a temporary name and not for all tables.

Let’s consider the following example to understand the table alias.

SELECT s.firstname, s.branch, teacher.firstname FROM student s INNER JOIN teacher ON s.branch = teacher.branch ORDER BY s.rollno asc;

Illustrate the result of the above statement using the following snapshot.

In the above statement for the ‘student’ table, we have created Alias s. So in this statement, we can use ‘s’ instead of the student table as it refers to the ‘student’ table.

Now we will add an alias for the ‘teacher’ table as ‘t’; look at the following example.

SELECT s.firstname, s.branch, t.firstname FROM student s INNER JOIN teacher t ON s.branch = t.branch ORDER BY s.rollno asc;

Illustrate the result of the above statement using the following snapshot.

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How Does A Flipped Classroom Work?

The buzz about flipped classrooms and blended learning environments hasn’t quieted down. Educators who haven’t yet experimented with these models are probably wondering if they’ll work in your classroom. Here are three FAQs to help you decide.

1. What are the differences between flipped, blended and traditional learning?

The traditional classroom is the one we’re all most familiar with. During class, teachers lecture and lead activities, then at home students do further enrichment and reinforcement activities.

Blended learning brings together elements of both traditional and flipped classrooms. Students may watch videos or use multimedia tools that explain or demonstrate concepts in or out of class, and teachers may continue to lecture and lead enrichment activities in the classroom. One of the benefits of a blended learning model is that by design it addresses multiple learning styles and modalities, ensuring that at least some activities will resonate with all of your students’ learning styles.

2. What do these learning modalities look like in practice?

One of the benefits teachers have mentioned is the ability to move some of the rote, skills-based instruction out of the classroom. In English classes, teachers can have students use vocabulary and grammar drill programs such as chúng tôi and GrammarBytes to build skills, then use class time for higher-level activities such as writing, revision and analysis of texts. Or, teachers can create videos that explain language arts concepts, as college instructor Dr. Jennifer Bernstein has done. She has shown these videos in class, finding that students were more engaged when she explained concepts on screen rather than in front of them. Her students can also watch the videos to review concepts outside of class.

Math teachers can flip their classrooms by using digital lessons to instruct students and allow them to practice skills at home using their personal or school-assigned devices before classroom discussions. Class time can then be used for whole-group and small-group activities that reinforce mathematical thinking. This combination of online-guided practice and observation by the teacher can help students not only better grasp fundamental math concepts but also see the fun and relevant side of math.

In science, the possibilities for fun in-class experiments really open up when teachers either flip the classroom or use blended learning methods. Not only can students see more science in action, but also they can have science experiences they couldn’t have in a traditional classroom. For example, seeing videos of space explorations or using virtual dissection tools and videos rather than in-class dissections.

3. Where can you find resources to flip your own classroom?

The rise in popularity of flipped and blended learning means there are many resources for instructional videos. You can find high-quality materials on YouTube, education-focused sites such as Knowmia, or targeted sites such as NeoK12. But even better, many of the textbooks you’re already using come with multimedia materials that are tied to your district’s or school’s educational goals already. And classroom technology systems also include carefully vetted and instructionally appropriate materials students can use both in class and out.

There’s a reason many educators are looking to the flipped classroom and blended learning — they can help students become more engaged in their learning and help the teacher make better use of class time.

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