# changing directory
pwd           # print working directory
cd PATH       # change directory (absolute or relative Path)
cd            # change directory to user home folder  
cd ~          # change directory to user home folder
cd /          # change directory to root folder
cd ..         # go one level up (to parent directory)
cd -          # switches working directory to previous wd (back and forth)
~             # home folder of current user
~dcts         # home folder of user "dcts"

# paths
/             # root folder
.             # current directory
./            # current relative path
..            # parent directory
../           # parent relative path

# listing content
ls              # lists all files and folders in the current directory
ls -a           # show also all .-files (hidden)
ls -l           # long format
ls -l -a        # two options
ls -la          # short version with two options
ls path1 path2  # ls can take also 2 inputs
ll              # show also hidden files (long format)
ll path1 path2  # ll can take also 2 inputs