The document discusses safety-critical applications in aerospace. It outlines 5 key things to know: 1) Which standards must be considered, such as DO-254 for electronics and DO-178 for software. 2) How to distinguish between Design Assurance Levels (DAL) from A to E based on failure rates. 3) How to achieve functional safety through redundancy, error detection/correction, and diverse/reliable system architectures. 4) How the Avionics Full-Duplex Switched Ethernet (AFDX) network provides reliable data transport in avionics. 5) How commercial off-the-shelf (COTS) components can help reduce costs through modular configurations and flexible/reusable IP cores.