ls tool is used to list the directories and files in linux. It can be used to list files in different way and can be categorized by date,size etc.
ls [ options ] [fileName]
-l : It lists in long list.
-a : It shows all the files.
-s : It shows size of file.
-h : It converts the data in human readable format.
ls -l :
It lists the content of directory in long list form. It gives detail about time,size,access etc. It can be done by `ll` command too in ubuntu.
ls -a :
It lists all the content even the even files too. It can be done by `la` command too in ubuntu.
ls -lash :
It is multi argument customized list.