Parentheses-Please help!

[GoPlayNOW]

I don't understand what the parentheses around tabs are. For example :


E:----------------------------------------
B:----------------------------------------
G:----------------------------------------
D:---7---(7)--6--5--4---------------------
A:---7---(7)--6--5--4---------------------
E:---7---(7)--6--5--4---------------------



:-/ I don't get it. Can anyone help me?

[ianb]

The notes in brackets are played much quieter than the others and are called ghost notes