9.2.1. ASCII and EBCDIC

Now, in computers we have to work with the character also because in numbers we are doing some arithmetic operation, but sometimes we have to work with number system because now you just see that in everywhere we are using computer you are writing letters also with the help of computer we have to say how to represent A, how to represent B and like that. So, here also in this representation we are saying that character representation saying that character c h a r a like that, but inside computer when we are storing it we cannot store c as it is everything has to be stored as a binary number not only binary number it is at the high voltage and low voltage already I have mention these things.

Computers primarily operate using binary code, but they also need to represent characters such as letters and symbols. To do this, each character must be assigned a unique binary code. This ensures that when you type 'A' or 'B,' the computer understands it as a particular binary number. Instead of treating characters as letters, they are represented using a numeric code, which corresponds to different voltage levels in the computer's hardware.

Think of this like a language where each letter in the alphabet corresponds to a number. For instance, 'A' might be 1, 'B' might be 2, and so on. When you write a word, you're actually writing down a series of numbers that represent those letters. The computer then reads these numbers to display the correct characters.

The first basic code is your ASCII, A S C I I American Standard Code for Information Interchange. So, this is a first code it is developed I think some of you may be knowing that when I am going to represent I think capital a or lower case a then we need some number I think to represent one of these numbers is your 65 in decimal numbers. So, for every number we are assigning a code and we are storing that particular code when we are going to store information.

ASCII is a character encoding standard used to represent text in computers. It assigns a unique number to each character; for instance, the uppercase 'A' is represented by the decimal number 65. Since ASCII uses 7 bits for its codes, it can represent up to 128 characters, including letters, digits, and certain special symbols. This allows computers to communicate and store text efficiently using a simple number system that they understand.

Imagine you are in a classroom where students each have a number assigned to them. If the teacher wants to call on a student, they use the number instead of the student's name. Similarly, in a computer, when you type a letter, it uses ASCII to translate your input into a corresponding number for processing.

But in case of EBCDIC, EBCDIC it is a just extended by 1 more bit it is an 8 bit code so; that means, my character size is increased by 2. So, it is becoming now 256 in ASCII it is your 128 it is your EBCDIC 256, but if you look into the entire universe entire globe there are a lot of symbols we should not only think about that English alphabets we should not think about only that numerals and the signs like + - and like that, but there are several languages and in every languages they are having several character.

EBCDIC, a character encoding system developed by IBM, uses 8 bits to represent each character, allowing for a broader range of characters, up to 256 different values. This expansion is essential for representing not only standard English letters and numbers but also characters from other languages and various symbols. This increased capacity is vital in our globalized world where computers need to handle diverse languages and symbols that ASCII cannot accommodate.

Think of EBCDIC like an extended library that contains not just English books but also books in every language and special characters. While an average library (ASCII) only holds a limited set of books (characters), the extended library (EBCDIC) can cater to a larger audience by including more diverse literature (symbols and characters) from around the globe.

So, finally, we want to represent each and every symbol every character to computer and we need a bigger code with 8 bit or 7 bit we cannot do it. So, for that the concept of UNICODE is coming in to picture. A unique numbers provided for each character. So, if you want to difference some character in computer then you have to approach this body then by looking into the nature of the character they will keep a unique code to this particular symbol or particular character and that is it can be used in computer.

With the demands for representing a vast array of characters globally, Unicode was developed to provide a comprehensive coding system that includes a unique number for every character across different languages and symbol systems. Unlike ASCII and EBCDIC, which have limited character sets, Unicode can represent thousands of characters, accommodating various scripts and symbols from languages worldwide. This makes it essential for global communication in computer systems.

Visualize Unicode as a universal translator for books from every corner of the world. While ASCII and EBCDIC might struggle to include books from various cultures, Unicode allows every book to be represented accurately in the library of a computer, ensuring anyone can access information regardless of the language or script.

--