Example
Before
Hi!
After
01001000 01101001 00100001
How text becomes binary
Text is encoded as UTF-8, and each byte is written as a group of eight 0s and 1s. English letters take one byte each. Accented letters take two bytes and emoji take four, so they produce more groups.
Decoding
Paste binary with spaces between the bytes, or as one continuous string of 0s and 1s, which is split into groups of eight.