Hostages are the main mechanic of hostage rescue missions. The Counter-Terrorists are usually assigned to find and escort them to a hostage escape zone (usually near or at their spawn) while the Terrorists are assigned to prevent that.
The hostage comes in at least a pair of female characters wearing grey suits and are indicated in the radar as green dots. Once a Counter-Terrorist meets up with a hostage, the hostage will then run to wherever the Counter-Terrorist goes, until they arrive at the rescue point.
To escort a hostage, a Counter-Terrorist must click E when near the hostage. In mobile, the player must move past a hostage to rescue it.