Wire Nut Connectors are the type most used with electrical work upon houses and the lighting systems. The inside of these are like a screw insert, in which when placed on the wires you wish to connect, they are placed within then the Wire Nut Connector is turned until tight, just a like a screw into wood. These give a little more security with connectors that don't require crimping, due to you can actually feel how tight the connection is made, and with the ridges inside, they are less likely to come loose.
