payload

Short definition from Wiktionary

Noun

1. 1
   That part of a cargo that produces revenue.
2. 2
   The total weight of passengers, crew, equipment, and cargo carried by an aircraft or spacecraft.
3. 3
   That part of a rocket, missile, propelled stinger, or torpedo that is not concerned with propulsion or guidance, such as a warhead or satellite.
4. 4
   The functional part of a computer virus or another type of malware program, rather than the part that spreads it.
5. 5
   The actual data in a data stream.