Newbie question on Signal & events

[William Pompei <pompeiw cs unibo it>]

I don't speak english very well so excuse me.
I've som question :

1)What is the difference betweeen signal and events?

2)Can I forget signal and use only events?

3)Are signal a simple manner of dealing with events? 
 (for example: The signal "clicked" referred to widget button can be
 managed with some event handler (I mean the event that generates the
 "clicked" signal) )

Thanks in advance

William