Because bytes tend to be longer, we'll want to use hex style mapping to represent bits. We know that hexadecimal is base 16 and bits are base 2 which translates to 4 bits = 1 hex.
Here's an example of why we want this case. If you have 16 bits, it looks like: 000011111111 but 0xFF is easier to read.
Here's a list of mapping for wanting only 1 bits: 0 -> 0x0 1 -> 0x1