The phone jack is the "best seller" of phone hardware, because there's at least one for every installed phone. You can choose from a huge variety: plain and fancy, good and bad, surface-mount and flush-mount, single-port and multi-port, Category 3 and Category 5e, two-pair, three-pair, four-pair...and more.
The jack at the top left is four-pair, surface-mount, Category 3. The jack below it on the left is designed for supporting a wall phone. In the center is a 4-port flush-mount plate, with four different "keystone" jack inserts.
Jacks are considered to be female connectors, despite their male name. Plugs are male. If you don't understand this, find someone of the opposite sex, both of you get naked, and then stand in front of a mirror.
Lots of info at www.ablecomm.com/colorcodes
and www.ablecomm.com/wiring.htm