The "CubeSat" is a type of miniaturized satellite for low earth orbit (LEO) space research and applications. One of these is typically made up of one or more 10+ 10+ 11.35 cm cubic units, and each unit has a mass of no more than 1.33 kilograms. In addition to being light and small, designers often use commercial off-the-shelf (COTS) electronic and structural components.

Although bunches of CubeSats have been launched on dedicated rockets, they are most often put into orbit in small numbers via the International Space Station or placed in orbit as secondary payloads.

It all started about 17 years ago when California Polytechnic State University (Cal Poly) and Stanford University developed CubeSat specifications in order to promote and develop the skills necessary for creating small satellites intended for LEO operations.

Until 2013, university education and research activities accounted for the majority of CubeSat launches. Since then, over half of CubeSat launches have been for non-academic purposes. Today, most newly deployed CubeSats are used for commercial or amateur projects.

CubeSat applications usually involve experiments which can be miniaturized and provide services for Earth observation and amateur radio applications. Some CubeSats are used to demonstrate spacecraft technologies or as feasibility demonstrators that can help to justify the cost of a larger satellite.

In some cases CubeSats may be used for low-cost scientific experiments that may verify underlying theories. In many cases, CubeSats represent a first national satellite for non-spacefaring nations. Finally, several future missions to the Moon and beyond are in the planning stages for CubeSats.

CubeSats have allowed the creation of an entire spaceflight subculture. Since it only takes one or two years to build and launch these tiny spacecraft, and the cost is only a small fraction of money spent on traditional satellites, many more people have entered the space exploitation community. For example, university students can see the results of their work while still working on degrees. Of course, these advantages have also led to important innovations.

It all started in 1999, when professors Jordi Puig-Suari of Cal Poly and Bob Twiggs of Stanford proposed a reference design for the CubeSat. Their goal was to enable graduate students to design, build, test and operate limited capabilities of artificial satellites within the time and financial constraints of a graduate degree program.

The first launched CubeSats were placed into orbit in June 2003 on a Russian Eurockot. A total of roughly 100 CubeSats have been placed into orbit. Many more such satellites are in the planning and development stages.