チートシート

OverAPI.com | Collecting All Cheat Sheets
http://overapi.com/

Emmet | Cheat Sheet
http://docs.emmet.io/cheat-sheet/

YUMコマンド
https://access.redhat.com/sites/default/files/attachments/rh_yum_cheatsheet_1214_jcs_print-ja.pdf