What are the Plugs for Ethernet?

I live in a 3 storey house and have no way of wiring ethernet cables to my room.

I was planning to buy something but I forgot the name.

It is a plug you put by the cable on your modem, then another plug you put where you need the ethernet port.

It uses the plug socket to transfer a better connection than you get from wireless.

Any help

@mattamomo:

A powerline adapter?

@GTR12:

That's the one.

Although looking at reviews they don't seem to be that great.

The ping people are getting from them is almost as bad if not worse than Wifi.

Anyone have any experience with them?

@mattamomo:

It entirely depends on how new your house/apartment is, old houses have worse power cables and internal wiring.