A CanSat is a type of sounding rocket payload used to teach space technology. It is similar to the technology used in miniaturized satellites. CanSats do not go into space, but instead are released at an altitude of about 1 kilometer, using a rocket or a balloon.

In CanSat competitions, the payload is required to fit inside the volume of a typical soda can (66 mm diameter and 115 mm height) and have a mass below 350 g. Antennas can be mounted externally, but the diameter can't increase until the CanSat has left the launch vehicle. The CanSats are deployed from small rocket at height which varies depending on the competition. CanSats are equipped with a recovery system, usually a parachute, to limit damage upon recovery and to allow the CanSat to be reused. CanSats are used to teach space technology, because of their inexpensive price and small volume.

In 1998, about 50 students and faculties from 12 universities from the United States and Japan met at a symposium held in Hawaii. It was the first "University Space Systems Symposium". Here, Bob Twiggs, professor emeritus at the Stanford University, proposed the initial idea of what later would become the nanosatellite projects. That idea was to launch a structure of the size of a soda can into space. Its volume should be around 350 milliliters and the mass, about 500 grams. This led to a project that began in 1999 called ARLISS, involving mostly American and Japanese Universities, carrying out the first launch on September, 11th of that year and continuing each year without interruption. The initial idea, still prevalent today, was to launch 3 satellites of 350 milliliters, or a satellite of greater volume. The means would be a rocket capable of moving 1.8 kilos and of ascending to 4000 meters, opening the door to low cost space flights -about $400. In 2000, the missions were very different: for instance, calculating the opening of a landing system using data provided by the barometer or making use of a differential GPS system. The project came to a more complex situation in 2001 when the ComeBack category was added, according to which the satellite should be directed to a particular target. This mission was very successful and, in 2002, students of Space Robotics Lab of the Tohoku University went up to 45 meters from the target and, in 2006, this figure dropped to 6 meters. Interest in this type of satellite has been growing and spreading. In 2003, the University of Tokyo placed into orbit two satellites CubeSat, satellites of a size slightly larger than the CanSats, and cube shaped. In recent years, several competitions have been developed following the same concept proposed by Prof. Bob Twiggs and reflected in ARLISS both national and internationally.

Some elements are shared by every CanSat:

The battery and/or solar panels supply power for operation of all systems. The systems must be able to be powered for four hours continuously and the battery should be easy to access. The most commonly used due to its performance and current-weight ratio are lithium polymer batteries (LiPo).^{[citation needed]}

The microprocessor is the heart of the satellite, as it is responsible for receiving signals from external sensors (such as the altimeter, accelerometer or the transmitter) and also processes them to act as programmed.

CanSats generally use microcontrollers (MCU) and MCU boards which include an internal memory for data storage alongside the microprocessor, useful for storing information from various sensors during the flight. Some of the most common MCU choices are:

Apart from the above-mentioned elements, others may be added in keeping with the mission it is entrusted with.