Autocompletion is a pretty nice feature when working in the shell. However the most commonly used Bourne-Again-Shell (Bash) does not use case-insensitive autocompletion by default like the less common zsh does.
But here’s the good news: You can configure it to do so.
If you want to set this system-wide, all you have to do is add the following line to your /etc/inputrc :
set completion-ignore-case on
You will need root privileges to do this. If you don’t have root access or you only want to set this for your account, just add the above line to your ~/.inputrc file (you probably will have to create it first).