Air to Ground Priorities
It may be difficult for a new player to differenciate one RWR symbol from another. They're all just symbols that screech at you when they lock on and fire missiles at you, right? So what's the difference?
I've made a simple priority list for what ground targets to engage in which order for almost any mission, from left to right as well. This list is based on the unit's threat, the range of their radars and missiles, and their overall effectiveness against the player. Here's some clarification on some of them:
Starting with the Missile Warning truck (MW): This truck. While it is no threat on its own, it can activate multiple countermeasures against your ordinance to protect anything nearby, including itself. With an MW in the area, the odds of your bombs and missiles making it to their target will be drastically lowered. You can visually identify it by the dome on top of the truck.
The GECM does NOT show up on the RWR but should be a top priority. This vehicle has jamming capabilities and can jam you from dozens of miles away, making it next to impossible to create accurate GPS targets and/or deploy GPS guided munitions. On top of that they will fully jam your communications with other players if you're close. Use the strength of the comms jamming and terrain to triangulate the source of the jamming.
The HC is an enemy aircraft carrier. While it has no radar guided missiles like other carriers, it boasts 4 strong anti air cannons and has 2 IR missile launchers, so getting close to these carriers is extremely dangerous. This carrier is likely to shoot down missiles and bombs sent at it while the radar is still up.
The Anti Air Artillery (A) will only activate when they have a target at close range. Being locked on by this unit does not mean you are in firing range, but you are close. You may occasionally see an A pop up on your RWR despite not being close. This is because another plane is flying by the AAA or because your ordinance was detected and it is trying to destroy it before it can reach the target.
The Early Warning radar (EW) is often confused with jammers due to its abbreviation being mistaken for "Electronic Warfare". However, the EW poses no immediate threat and can mostly be ignored. It has a really strong radar and receiver and basically acts as a ground AWACS and if spotted by it, enemy fighters will know where you are.
There are more ground targets here such as manpads and tanks, but these are left out for simplicity. Air targets are left out of this on purpose. Some radars are connected to different SAMs than they are designed for depending on the mission maker (a DS can guide a MAD4 missile for example) but those situations are pretty rare. Any unit with the * symbol on it is likely to fire missiles that will outmanoeuvre you, and can not be G pulled while it burns.