The ability of electricity to be turned on or off by a switch is paramount to the operation of all things electrical. to use electricity to switch on or off via relay or transistor allows for one action to cause something else to happen. When you add enough of these together you get logic gates. Add enough logic gates together an you have a computer. Switching is important in all levels of electronics.
Nice homework answer.
Think the teacher will find this site if they copy that answer into Google?
www.google.co.uk/search Funnily enough, yeah.
I wanted to be helpful enough to point in the right direction - perhaps to help search for more information...but not enough to copy-paste-instant-a+
No, I think you've answered it beautifully, in the sense you mean ! Steve
A switch is in need of an index finger or thumb to occasionally change the state of things.
Generally, they just need love and attention, and perhaps a bit of kibble every now and then.