Swimming Terms explained - BAG points or BAGCAT points
The performances of swimmers are measured and compared across a range of events. 
Points are based on a FINA scoring model. 
The points scored for particular times in individual events are based on swimmers relative performance to top 10 historic all time performances.

Some competitions (eg Essex County Age Group Championships or Eastern Region Championships) ‘Top Boy’ or ‘Top Girl’ trophies are awarded.  These are based on the total BAGCAT points scored by swimmers in a selection of events. This was originally intended to encourage younger swimmers to compete in a wide range of events.  To make things further complicated, the events are grouped together and only the swimmers highest point score in each group of events will count.  These are usually grouped as best sprint (50m), best 100m, best Individual Medley, best distance (200m+) and best non-Freestyle performance (known as a ‘Form Stroke’). The stroke groups change as swimmers get older.

See attached table for the event groupings for particulars ages and competition levels.    
Go to To: - BAGCAT points calculator to see potential points awarded for a particular event, swimmer, age and time.