This page is an extension of 56 Tactical Patterns That All Chess Players Should Know.
A weak back rank occurs when a king is exposed on the back rank. Back-rank weaknesses are among the most common tactical motifs in practical chess.
Here are three examples of targeting a Weak Back Rank.
Example #1

1. Qxc6 Rxc6? 2. Rd8+
Example #2

1. Ne2+
Example #3

1. Qxe5 Qxe5 2. Nxf7+