The title says it all.
I'm just starting to go through the existence-proof of the quot scheme (http://www.math.utah.edu/~bertram/courses/hilbert/ps/hilbert.ps). On page 7, almost at the bottm of the page a scheme is defined as the zero locus of a homomorphism of sheaves.
What exactly is the zero locus of a sheaf homomorphism?
Greetings
Dan