What is Signal, the app Trump’s team used to chat about Yemen war plans

The Senate Intelligence Committee heard testimony on Tuesday from key players involved in a group chat on the messaging app Signal, in which the U.S.’s highly sensitive plans to bomb Houthi targets in Yemen were discussed inadvertently with a journalist. President Trump said that his administration would investigate the government’s use of Signal. CBS News contributor and former CIA official Andrew Boyd has more on what it is and how it’s used.