So, I'm studing now at computation university in my city and I'm gonna tell u a little bit about this so important thing for computing that is the ASCII table, that menas American Standard Code of Information Interchange.
So, we know that all the information in the computer is stored as a binary code, that's the only thing the computer actually 'understands'. Therefore there is a association between some 0-1 combinations and letters and that's called the ASCII table. It's essencial for computing.Anyway, there is a image below with the non-extended version of the table and below the extended version.
The codes are in Decimal and hexadecimal.
Ascii Table 1
Ascii Table 2