Today we look at character encoding. There are many encoding standards both in
the past and present. In this episode we take a look at ASCII, American
Standard Code for Information Interchange. It was developed in the 1960 and continues
to be relevant today. ASCII encodes 95 printable characters and
33 control characters. As a result, every character takes up 7 bits
of space for 128 characters to each have its own unique representation. The very first printable character is space,
as in the character that gets generated when you press the space bar. The English alphabet begins with capital A.
B would be one number later, and so forth. Lower case alphabet is exactly 32 positions
after the upper case alphabet. Given the fact that modern computers process
information at a multiple of 8 bits as opposed to 7 bits, several extensions to vanilla ASCII
emerged to take advantage of the unused 8th bit. Initially, the 8th bit was used as a parity
bit for error checking. However, as transmission reliability increased
and the responsibility for error handling shifted elsewhere, the 8th bit was then used
to extend the number of characters ASCII can represent. With virtually all extensions, to preserve
backward compatibility, when the 8th bit is set to 0, it functions exactly as vanilla
ASCII. However, when the 8th bit is set to 1, all
bets are off. In Indian Script Code for Information Interchange,
this number maps to this character. However, the exact same encoding maps to this
character in Vietnam Standard Code for Information Interchange. The operator must know which code page to
use to decode characters encoded in extended ASCII. It’s easy to see how this can lead to confusion
and frustration. Also, 8 bits can encode at most 256 characters. What about languages that use thousands of
characters? Is there a Chinese Standard Code for Information
Interchange? Many have risen to this challenge and the
prevailing encoding standard that overcomes these issues is Unicode, which we will look
at in the next episode. Thanks for watching. I’d like to give special thanks to chicken
wings, who did not sponsor this video. I had ten of them last night and I have never
felt more bloated. But they were delish. This is an Endian Tribe production. All rights very much reserved.

Character Encoding (ASCII) Explained in Haste | How Computers Store English Letters
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