3. String storage

ASCII is a very popular standard for storing characters and groups of characters i.e. strings.

It is a 1 byte per character system. The string:

                    MyString ="hello"

is five characters in length and it needs 5 bytes of storage.

ASCII is used for standard 'Latin' characters (this includes English). It uses denary values 0-255 and can store:

• upper case letters
• lower case letters
• some control characters
• symbols
• a few accented characters.

However, the world speaks many languages which use non-Latin characters such as Ў (a Russian cyrillic letter). To handle this, Unicode was developed. This is 2 bytes per character (Unicode-16).

Many computer languages support both, and will switch storage size depending if a single byte or a 2 byte unicode version is needed.

Python for example uses Unicode by default, but if the character is part of the ASCII set it uses a single byte.

For example, the string

                          mystring = helЎlo

is six characters long and it takes 7 bytes of storage because the Ў cyrillic character needs 2 bytes.