“ls” is a command that shows a list of all files and directories in a current directory.
“ls *.txt” shows all files name that matches the string before .txt;
“ls -l” is a command that shows the long form of a list with a date and time indicator of file modification, the size of the file, etc;
“ls -rtl” (list by reversed time of modifications)
“touch” is a command to create an empty file with a name.
If you want to create a file, and you don’t care about a name, the name is usually “foo,” then “bar,” “baz,” “qux,” “quux,” etc.
