gzip.txt

# gzip only operates on SINGLE FILES.
# use `tar z` for directories with \e[38;5;201mc\e[0mreate or e\e[38;5;201mx\e[0mtract

-d  decompress                 # aka `gunzip`
-c  redirect output to STDOUT
-t  verify archive integrity
-l  show uncompressed filesize and compression ratio. \e[31;1mNB:\e[33;22m this fails for input files over 4 GB, since the
    original filesize is stored in 4 bytes. Higher filesizes are stored as filesize modulo 2^32, and can
    hence show negative compression ratios.\e[0m
# default behaviour is to replace the old file with the [de]compressed version. To keep the input file,
# recent version of gzip:
-k  --keep, [de]compress to a new file
# older versions of gzip output to stdout (-c) and redirect to a file
gzip -c file > file.gz

zcat == gzip -dc == gunzip -c == decompress to STDOUT
if you want to zcat | less, \e[38;5;202mzless\e[0m is also a thing