The name of this encoding comes directly from the mathematical definition of bases - we have 64 characters that represent numbers.

The Base64 character set contains:

• 26 uppercase letters: A - Z
• 26 lowercase letters: a - z
• 10 numbers: 0 - 9
• + and / for new lines

When the computer converts Base64 characters to binary, each Base64 character represents 6 bits of information.

If we were to Base64 encode a string say 'Python' then we would follow these steps:

1. Take the ASCII value of each character in the string.
   The ASCII values of the characters P, y, t, h, o, n are 15, 50, 45, 33, 40, 39 respectively
2. Calculate the 8-bit binary equivalent of the ASCII values
   01010000 01111001 01110100 01101000 01101111 01101110
3. Convert the 8-bit chunks into chunks of 6 bits by simply re-grouping the digits
   010100 000111 100101 110100 011010 000110 111101 101110
4. Convert the 6-bit binary groups to their respective decimal values
   20 7 37 52 26 6 61 46
5. Using a base64 encoding table, assign the respective base64 character for each decimal value
   20 refers to U, 7 to H so on so final string is UHl0aG9u