The easiest is to use a cheat sheet when you are not sure about how to use a command.
# download cheat.sh
curl https://cht.sh/:cht.sh > /usr/bin/cht.sh
# make it executable
chmod +x /usr/bin/cht.sh
# add an alias for cht.sh
echo "alias cheat='cht.sh'" >> .bashrc
# apply new alias
source .bashrccheat gzipuser@server:~# cheat gzip
# To create a *.gz compressed file
gzip test.txt
# To create a *.gz compressed file to a specific location using -c option (standard out)
gzip -c test.txt > test_custom.txt.gz
# To uncompress a *.gz file
gzip -d test.txt.gz
# Display compression ratio of the compressed file using gzip -l
gzip -l *.gz
# Recursively compress all the files under a specified directory
gzip -r documents_directory
# To create a *.gz compressed file and keep the original
gzip < test.txt > test.txt.gz
