Explanation
"ls" is used for listing out the contents of a directory (or folder). It's much more powerful than just giving you a list, you can also change the order, get extra information and similar.
Examples
# Basic example
ls
# This will give you a list of the files and folders.# One file/folder per line
ls -l
# This will give you a list of the files and folders, but listed out one item per line.# Include hidden files and folders
ls -a
# This will give you a list of the files and folders, including the hidden ones.# Combining options
ls -la
# This will give you a list of the files and folders, including the hidden ones. The items will be listed out one per line.# All files in descending orders
ls -larth
# -l = one item per line
# -a = include hidden files and folders
# -r = reversed order
# -t = sort by time (modified)
# -h = include the size of the files