The use for the electromagnet is to pick up scraps in junk yards.
Electromagnets can be 'turned off' so you can pick something up and drop it in another place. You can't do that with a permanent magnet.
They have other uses like locks, relays switches.
Look up electromagnets in wikipedia.
To not have to walk
so you can communicate
to color
The purpose of inventing the machine gun was to have better fire power during the wars to defends places and win positions and the war.
Slicing meat.
It was to replace horses as a means of transportation.
To take pictures and to capture the memorable moments.
To ease healing and avoid infection.
So people can listen to amazing music.
It was to listen to music and now other things.
so you dont have to look at it and it doesnt smell.
Alexander Graham Bell invented the telephone.