file(1)
xxd(1)
cut(1)
lzma(1)
ls(1)
rev(1)
ar(1)
xz(1)
grep(1)
tar(1)
sha384sum(1)
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head(1)
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unzip(1)
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tr(1)
base64(1)
bzip2(1)
base64 has, as the name implies, 64 unique characters that can represent different values. the characters are A-Z, a-z, 0-9, +, /.
A-Z represents values 0-25 in decimal.
a-z represents values 26-51.
0-9 represents 52-61.
+ = 62, and / = 63.