F1 Hybrid?

I see this term alot, and wanted to know if anybody could tell me what it means? I'm assuming it means it's of the highest quality, but that's just a guess.

When two stable strains are crossed, the next generation of plants from the seeds produced will be called the F1 generation. The idea and hope is that the best qualities of the paternal and maternal plants are expressed in this F1 generation. Hybrid vigor is often used to describe this.

Awesome, thanks.