There are currently three stand-alone as well as one hybrid Game Mode available in Overwatch. A new mode has been added in the beta in February, 2016.[1]
Escort
is a Game Mode in which the Attacking team's objective is to move the
payload to a delivery point, while the Defenders must halt the
Attackers' progress until time runs out.
Escort maps:
Assault is a Game Mode in which the Attacking and Defending teams must attempt to take or defend capture points across the map.
Both
teams battle over control of the map, one team on offense, the other on
defense. The attackers' goal is to capture critical objectives, while
the defenders must maintain control over them until time runs out.
Assault maps:
The
only currently available hybrid Game Mode starts with an Assault and
ends with an Escort section. These two parts behave exactly as their
stand-alone Game Modes do.
Hybrid maps:
On
Control maps, two teams fight over a series of objective areas in a
best-of-three format. When a team is in control of the round’s
objective area, they will make progress toward capturing it, and
whichever team gets to 100% first wins the round. Each round (up to 3
total) will feature a new objective area located in a different part of
the map.
Control maps: