Q:

Taping and finishing

Gypsum boards without taping and finishing.
What does taping and finishing mean? 

Materials - tape and finishes
Action - taping the board and finishing the board.
Possibly something else.

A:

Gypsum boards (called "drywall" in the United States) are prefabricated sheets of gypsum between smooth paper covers; they are nailed to the timbers (studs) of interior walls and take the place of old-fashioned lath-and-plaster covering.
Once the drywall boards have been put up, it is necessary to hide the seams between them before painting, so the wall appears completely smooth and unbroken. This process is called finishing the drywall. This involves covering the seams with drywall tape and several layers of joint compound ("mud" in the US) spread very thin; once the compound has dried the surface is sanded.
The pictures below depict mounting, taping, and 'mudding' drywall. They're drawn from familyhandyman.com, where you can read about this in greater detail.

