You can type:
ls -FThis appends a slash (/) to each subdirectory name, and an asterisk (*) to the name of each executable file. If you want the -F flag in effect every time you give an ls command, make an alias for ls, like this:
alias ls='ls -F'Be sure to include the quotation marks. You can also put this alias command in your .bashrc file so the alias goes into effect automatically every time you log in.