How to backup a file in Linux/Unix

You might be working on a file that is important to you and do not want to mess it up, the best thing to do is backup the file and then do what you want to do just to be on the safe side, lets see example of how to do this using Linux/Unix command,

Option 1: Backup a file using cp command as a new file

# cat my-important-file.txt 

This is one of my 
very important 
text file.

As you can see I have a file that I want to change, but before change it I want to take a backup of It, lets do that using the cp command,

# cp my-important-file.txt my-important-file-backup.txt

As you can see using the copy command, I took a backup of the file my-important-file.txt in a new file that I named as my-important-file-backup.txt, now lets see if the content of the file is same or not,

cat my-important-file-backup.txt 
This is one of my 
very important 
text file.

Option 2: Backup a file with the same name at a different location

# cp my-important-file.txt /home/   
# cd /home/
# ls
my-important-file.txt

# cat my-important-file.txt 
This is one of my 
very important 
text file.