Group of small spacecrafts

A spacecraft is a vehicle or machine designed to fly in outer space. Spacecraft are used for a variety of purposes, including communications, earth observation, meteorology, navigation, space colonization, planetary exploration, and transportation of humans and cargo. All spacecraft except single-stage-to-orbit vehicles cannot get into space on their own, and require a launch vehicle (carrier rocket).
Spacecraft

The size and cost of spacecraft vary depending on the application; some you can hold in your hand while others like Hubble are as big as a school bus. Small spacecraft (SmallSats) focus on spacecraft with a mass less than 180 kilograms and about the size of a large kitchen fridge. Even with small spacecraft, there is a large variety of size and mass that can be differentiated
What a small spacecrafts

Group of small spacecrafts:

The term "small satellite",[2] or sometimes "minisatellite", often refers to an artificial satellite with a wet mass (including fuel) between 100 and 180 kg 5][6] but in other usage has come to mean any satellite under 180 kg 3]
Minisatellite

The term "microsatellite" or "microsat" is usually applied to the name of an artificial satellite with a wet mass between 10 and 100 kg 2][5][6] However, this is not an official convention and sometimes those terms can refer to satellites larger than that, or smaller than that .2] Sometimes designs or proposed designs from some satellites of these types have microsatellites working together or in a formation.[12] The generic term "small satellite" or "smallsat" is also sometimes used,[8] as is "satlet".[13]
Microsatellite

The term "nanosatellite" or "nanosat" is applied to an artificial satellite with a wet mass between 1 and 10 kg (2.2 and 22.0 lb).[2][5][6] Designs and proposed designs of these types may be launched individually, or they may have multiple nanosatellites working together or in formation, in which case, sometimes the term "satellite swarm"[20] or "fractionated spacecraft" may be applied. Some designs require a larger "mother" satellite for communication with ground controllers or for launching and docking with nanosatellites.
Nanosatellite

The term "picosatellite" or "picosat" (not to be confused with the PicoSAT series of microsatellites) is usually applied to artificial satellites with a wet mass between 0.1 and 1 kg (0.22 and 2.2 lb),[5][6] although it is sometimes used to refer to any satellite that is under 1 kg in launch mass.[2] Again, designs and proposed designs of these types usually have multiple picosatellites working together or in formation (sometimes the term "swarm" is applied). Some designs require a larger "mother" satellite for communication with ground controllers or for launching and docking with picosatellites. The CubeSatdesign, with approximately 1 kilogram (2.2 lb) mass, is an example of a large picosatellite (or minimum nanosat).
Picosatellite