Importance of Command Line Basics

Recently I had to work with a client who was a Mac user and I'm a Windows type of a bloke.  I accessed the client's machine over remote desktop, for a practical tutoring lesson on how to setup and use build tools. It took me by surprise, a bit, when I saw that he was using Mac OS X I though I might embarrass myself , but then I remembered that real ninjas don't panic so I just opened up the terminal, instead of poking around the file explorer (File Finder I believe it's called on Mac).

After that it was mostly smooth sailing. I've been using Unix commands via Git Bash on Windows for a quite a while and it sure has paid off.  There are plenty of operating systems out there and each has their own unique Graphical User Interface and it's hard to know your way around all of them. One of the advantages of knowing the command line is that is it's an universal tool, especially Unix commands, same command will work on both Linux and Mac. Unix command line can be also used on Windows, with tools like Git Bash, or even natively by using Windows PowerShell. Unless you're still using Windows 98... 

Command line can seems scary and overwhelming at first, but as developers we don't need to learn all of the commands, just a small portion, like moving around the file system, making new directories and files, recriminating and deleting, to name a few. Even when it comes to custom CLI's most of the time you'll be using maybe 10-20% of the available commands. Obviously administrators and dev ops people need to know more commands by hearth, but developers have it easy, most of the time.

Bellow is a list of most commonly used commands, thanks for stopping by.

Command	Description
ls	Lists all files and directories in the present working directory
ls - R	Lists files in sub-directories as well
ls - a	Lists hidden files as well
ls - al	Lists files and directories with detailed information like permissions, size, owner, etc.
cat > filename	Creates a new file
cat filename	Displays the file content
cat file file2 > file3	Joins two files (file1, file2) and stores the output in a new file (file3)
mv  file "new file path"	Moves the files to the new location
mv filename new_file_name	Renames the file to a new filename
sudo	Allows regular users to run programs with the security privileges of the superuser or root
rm	Deletes a file
man	Gives help information on a command
history	Gives a list of all past commands typed in the current terminal session
clear	Clears the terminal
mkdir	Creates a new directory in the present working directory
mkdir	Create a new directory at the specified path
rmdir	Deletes a directory
mv	Renames a directory
pr -x	Divides the file into x columns
pr -h	Assigns a header to the file
pr -n	Denotes the file with Line Numbers
lp -nc lpr c	Prints "c" copies of the File
lp -d lp -P	Specifies name of the printer
apt-get	Command used to install and update packages
mail -s 'subject' -c 'cc-address' -b 'bcc-address' 'to-address'	Command to send email
mail -s "Subject" to-address < Filename	Command to send email with attachment