Definitions: Interference

Let's start with interference, since this is a relatively non-trivial concept compared to say pinning and forking.

Interference: The interfering piece moves with it's own threat forcing it's own capture. The capturing piece blocks the line of one of it's own pieces which is defending a different threat.

Reinfeld Position #583

White to move

White plays 1. Rd5 threatening Rxd8 mating.
1. ... exd5 interfering with the Queen's protection of the Rook, 2. Qxd8#
1. ... Rxd5 interfering with the Rook's protection of the back rank, 2. Qe8#
1. ... Qxd5 interfering with the Queen's protection of a1-h8 diagonal, 2. Qf6#