The Time Base meta information can be found in many different file types, such as audio, image, video and data files. The time base is usually responsible for the display of data during a specific time. Different kinds of data sometimes have to be displayed at the same time. The Time Base takes care of the simultaneous transmission of this data.
In some cases, the time base is required by the file format or container. Then, it will be specifically set within the file. If the Time Base is not required, however, it may still be present, containing a default value.