ASCII

ACII (pronounced ass-key) is the code used by all personal computers. It was first used in the US, hence the name American Standard Code for Information Interchange. However, it is now used as an international in code. It is very similar ISO 8859 Latin 1 encoding, which is used for the internet.

ASCII code uses 7 bits to allow text to be stored in binary as individual characters. Sometimes an 8th bit is also add on to the left hand side of the current byte to allow other characers to also be included, such as punctuation symbols. The 8th bit may also have been used for error checking (known in this case as parity bits). These examples are represented as follows:

Character 7-bit ASCII Binary 8-bit EBCDIC Binary
A 1000001 11000001
B 1000010 11000010
C 1000011 11000011
D 1000100 11000100
W 1010111 11100110
X 1011000 11100111
Y 1011001 11101000
Z 1011010 11101001
0 0110000 11110000
1 0110001 11110001
2 0110010 11110010
3 0110011 11110011
4 0110100 11110100
5 0110101 11110101
6 0110110 11110110
7 0110111 11110111
8 0111000 11111000
9 0111001 11111001
Space 00100000
? 00111111

An extensive chart can be found here. This shows the meaning of each new line of ASCII binary code.
From this, we can see that if a computer were to sort the ASCII code into numerical order, the letters will automatically be placed in alphabetical order. Aswell as this, upper case letters will be placed first, as each lower case letter is 32 places after its upper case equivalent.

Controll characters such as NULL (00000000) were also used in ASCII code previously, however they have little use now. For example, NULL was used to indicate that no holes needed to be punched in paper (as a hole signified a 1 on paper and no hole represented a 0). ASCII code became very successful very fast, as it set the standard for all computer to read the same basic values from the same combinations. Because of this there has even been a 16 bit code created, known as UNICODE.

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