A device with a pivoted support that allows an object to rotate about a single axis. Essentially it keeps things stable while the larger parts move; in ships the cup holders have a gimbal so it stays straight up while the ship pitches and rolls in the sea. This same effect is used for cameras, allowing the camera to track an object while the shooting angles change. It takes a 3 axis stabilization unit to achieve the basic level needed for improved video. A gimbal makes it seem like the camera is floating through the air while it tracks a subject.
Today the basic device has been improved upon with brushless motors and inertial measurement units (IMU). This IMU allows a gimbal to process the information using a guidance algorithm. It can tell the difference between deliberate movement and the unwanted shakes. The unwanted parts are dealt with by adjustments to the motors. These gimbals can be mounted onto vehicles too where vibration is expected and resulting in a beautiful steady shot.
There are many gimbals on the market, with various features and also different build qualities. The sizes vary as well depending on what camera types they have been built for. Mobile gimbals can be found for all cameras from mobile phone cameras to the Red Digital Cinema line.
Mobile gimbals are available for many different prices depending on the size, features and brand. Known brands include DJI and Zhiyun.