02 What is the Base16 encoding?

https://en.wikipedia.org/wiki/Hexadecimal

Base16 describes a method in which binary data is converted into a string consisting of only 16 different ASCII characters.

Each byte (i.e. 8 bits) is divided into two 4-bit groups. Each of these groups corresponds to a number between 0 and 15. These numbers are converted into “printable ASCII characters” using a conversion table.