If you want something to happen when you login, then there are several ways to do that, but that is not what this post is about.
With a Raspberry PI it can be very nice to configure the device to have a service running or to do some operation which you want to happen at boot and without user interaction, to do this use:
sudo vi /etc/rc.local
If you have a problem with this script or you need to break out of it running (similar to CTRL+C in a shell) then use:
alt + print screen + K
Have a nice day!
I like science and writing software.