These are my personal notes to prepare for the LFCS exam.
This book consists of a detailed guide for each topic in the official checklist of domains the candidates are requested to master in order to pass the exam.
These notes has been collected from a wide range of sources available on the web and partially re-elaborated by me, plus some additional topics of interest for a developer/sysadmin (still in progress): even if you are not interested in the certification at all (but curious about *nix systems), you may nevertheless find useful the guides in the first domain (Essential Commands) since they cover the very basic commands to work inside a bash shell.
Please, note that I took into consideration only Ubuntu (18.04/20.04) as exam environment. Things can be different in CentOS.
