ls [directory / filename]

• List directory contents (including subdirectories).
• Works like the dir command in Windows.
• The -l flag lists detailed file / directory information.
• Use -a to list hidden files.
• Hidden folders / files in Unix start with a ..
• E.g. .git/ or .gitignore.

cd [directory name]

• Changes directory to [directory name].
• If not given a destination, defaults to the user's home directory (~).
• You can specify both absolute and relative paths.

File Paths

• Absolute paths start at / (the global root).
• E.g. cd /home/sven/Desktop
• Relative paths start at the current directory.
• cd Desktop, if you were already at /home/sven

Relative Path Shortcuts

# start by navigating to a directory
$ cd /usr/local/src
# the command below puts us at /home/sven, same as cd ~
$ cd
# the command below puts us back at /usr/local/src
$ cd -
# the command below takes us to the parent directory, /usr/local
$ cd ..

mkdir [flags] <dir1> <dir2> ... <dirN>

• Can use relative or absolute paths.
• a.k.a. you are not restricted to making directories in the current working directory.
• Need to specify at least one directory name.
• Can specify multiple, separated by spaces.
• The -p flag is commonly used in scripts.
• Makes all parent directories if they do not exist.
• Convenient because if the directory exists, mkdir will not fail.

rm [flags] <filename>

• Removes the file <filename>
• Removes multiple files with "wildcards":
• Remove every file in the current directory: rm *
• Remove every .jpg in the current directory: rm *.jpg
• Prompt before deletion: rm -i <filename>

rmdir [flags] <directory>

• Removes an empty directory.
• Throws an error if the directory is not empty.
• You are encouraged to use this command: failing on non-empty can and will save you!

Note: to delete a directory and all of its subdirectories:

• rm -r <directory>
• -r tells rm to recurse.
• e.g. rm -r /home/sven/oldstuff

cp [flags] <file> <destination>

• Copies from one location to another.
• To copy multiple files, use wildcards (such as *).
• To copy a complete directory:
• cp -r <src> <dest>

mv [flags] <source> <destination>

• Moves a file or directory from one place to another.
• Also used for renaming, just move from <oldname> to <newname>
• e.g. mv badFolderName correctName
• Unlike the cp command, mv automatically recurses for directories.

more <filename>

• Scrolls through one page at a time.
• Program exits when end is reached.

less <filename>

• Scrolls pages or lines (mouse wheel, space bar, and arrows).
• Program does not exit when end is reached.

head -[numlines] <filename>

• Prints the first numlines of the file.
• e.g. head -19 someFile.txt prints the first 19 lines.

tail -[numlines] <filename>

• Prints the last numlines of the file.
• e.g. tail -19 someFile.txt prints the last 19 lines.