Symbolic expressions (more commonly SEXPs) are used by FreeSpace missions.
- Retail SEXPs for SEXPs that are used by FreeSpace 2 v1.2.
- SCP SEXPs for SEXPs that were implemented by the Source Code Project.
- Dynamic SEXPs for documentation on how to add custom SEXPs to a mod. These will appear as usual in the mission editor but the mod can define what the SEXP does.