Fencing is a sport where refereeing is Ultimately important and ‘interpretation’ is fundamental to the match decision….
All 3 weapons have their unique technical points ( and are taught to include them ).
Here is one of them for Foil courtesy of Youtube:  Link 
The definitions / interpretations may have changed over the years.

What is yours for this one? ! 

For those who need to know the answer : Link as defined by Techneical Directoire  Mr Ioan Popp.

There are a number of Fencing clips now available via the web, and you may have found it difficult to find examples prior to the ability of “being able to broadcast yourself”… now it seems anyone can do it!
Good examples (previous example shown here) and others…unfortunately can be seen….
For discerning viewers, A Qualified Coach is a good person to ask if your not sure.