Grow Your Own Magazine

I'm not a scientist and I was hoping someone could explain in laymen's terms about the reason for and implications of using F1 hybrids. I must admit that I don't fully know what it means.

When I ordered all my seeds a few weeks back I was thinking of just getting squash seeds from a squash, but a gardeney friend advised me not to incase the squash was an F1 hybrid and therefore might not grow. Out of all the seeds I have in my possession now, some of them are F1 hybrid varieties and some are not.

Sorry for being thick, but how does it all work and what is it for? And is there some kind of environmental implication, something to do with continuity of varieties or something to do with the cycle of growing new seeds or something?

Any explanation would be much appreciated.

Many thanks for that. I'll post my question over there