GUI (graphical user interface) is easy to use and goodlooking. But CLI (command line interface) is faster and easier to automate. Advantages of Command Line over Graphics Graphics are fancy but lack clarity and prone to errors and crashes and uses alot of resources (RAM, CPU and GPU). Here are some advantages. Lightweight Text Interface If you accomplish a task like converting mp4 to mp3 on command line using ffmpeg, it will be faster than using any other GUI program such as Format Factory (for Windows OS).

First step: create a utilities.sh file to add all your bash functions in it. 2nd step: add your bash function/s like this. ## utilities.sh convertMP4toMP3(){ echo -n "Enter source mp4 file : " read sourceFile echo -n "Enter destination mp3 file : " read destFile avconv -i $sourceFile -vn -acodec libmp3lame -ac 2 -ab 160k -ar 48000 $destFile } I created a bash function to convert mp4 video file to mp3 audio file from command line.