Research and teaching appointments advance the development of graduate students by giving them experience in scholarship and instruction while also providing an income.
Most graduate students at MIT are supported by appointments as research or teaching assistants. See RA, TA, & IG appointments for more information about the responsibilities for these roles on the OGE website.
For tax purposes, research assistant and teaching assistant stipends are considered earned income as a result of the services rendered. As such, the Institute is obliged to withhold federal and Massachusetts income taxes from the stipends of teaching and research assistants. You can learn more about the tax implications of research and teaching assistantships on the OGE website.