It’s a folder containing your build information, targets of debug and release as well as projects index.
Why do we delete the derived data ?
It helps to get rid of some code compilations issues, slow project and constant reindexing issue.
Step1:
Open Xcode and choose Preferences
Select 'Locations' tab.
As shown below, you can click on the arrow to find the derived data folder.
You can see a folder 'Derived Data' Right click and Delete folder.