Described as "intimate video performances recorded live" that pretty well sums it up. Bands big and small, famous and less well-known, come to perform in the offices of National Public Radio behind the desk of the host of All Songs Considered Bob Boilen. One of my favorites was the video of a more innocent Adele from February 2011.
Another great example is Common who performed at a special edition Tiny Desk in the Barack Obama White House in 2016.
Another weird example is The Blue Man Group, also from 2016.
Search the website for a performance that interests you: www.npr.org/series/tiny-desk-concerts/