ASCII Codes

Computers do not recognize letters, text, or words. They only deal with numbers. To get computers to work with text, we have to represent each character as a number. The text files you read and write are actually stored, loaded into memory, and transposed into numbers. When the file is shown on your screen, the numbers are transposed again into letters and text. The first 31 ASCII codes control commands or nonprintable characters that control how the data will be interpreted. ASCII is a computer code originally based on the letters of the English alphabet.

It is an acronym for American Standard Code for Information Interchange and is used to represent text in computers, communications equipment, and texting devices. Each letter and number is given an ASCII code. Certain commands are also given an ASCII code. For example, the ASCII code for A is 65, and the ASCII code for 4 is 52. Work on the ASCII code started in 1960, and in 1968 President Lyndon B Johnson mandated that all computers purchased by the United States government support ASCII code. Computers use ASCII code to communicate with each other. http://www. ascii-code. com/

The following table shows the ASCII code for letters, numbers, and commands. The ASCII code for the word “Bears” would be 66 101 97 114 115. Note that the ASCII code is different for uppercase and lowercase letters. B: 66 e: 101 a: 97 r: 114 s: 115 By the same token- the code: 68 105 115 110 99 121 would read “Disney” once transposed. 68: D 105: i 115: s 110: n 99: e 121: y You could see these as an example of how we use our computers to communicate. We type letters and words, the computer transposes them into a code that it can understand and sends it to your friend’s computer.

Your friend’s computer understands the code and transposes it back into text so your friend can read what you wrote. [pic] http://www.tntbasic. com/learn/help/guides/asciicodesexplained.htm Why is ASCII code important? Because ASCII files can be used as a common denominator for data conversions. Let’s say Program A can’t convert its data to the format of program B. But if both programs can input and output ASCII code, then the conversion may still be possible. Most e-mail transmissions are limited to ASCII characters.

Because of this, it is not possible to use special formattings such as Italics or underlines. This is also why graphic files, music, spreadsheets, or documents with non-ASCII characters in them must be sent as attachments to the e-mail. When they reach their destination, they will be “decoded” for use. http://www.telacommunications.com/nutshell/ascii. htm These words come together to make sentences. So for example: “Who let the dogs out? ” would look like this: 87 104 111 32 108 101 116 32 116 104 101 32 100 111 103 115 32 111 117 116 63 87 104 111: Who 2: space bar 108 101 116: let 32: space bar 116 104 101: the 32: space bar 100 111 103: dogs 32: space bar 111 117 116 63: out? S

If someone tries to decode a document containing such raw data using ASCII, they will probably get a response that the file is corrupted. There are programs online that can transfer between ASCII code and binary code. http://www. coreftp. com/docs/web1/Ascii_vs_Binary_transfers. htm There is also an upper case ASCII table which is not officially recognized. It tends to vary based on the computer or font being used. Some characters in this table are more common than others. [pic] In short, ASCII code is how our computers operate, process information, and communicate with each other.