multi words seperated by a -

[ahmadizat]

some times I encounter a group of words ( mostly two ) seperated by a (-)
that acts as a single word such as in the following examples:

"computer-based systems."
"the .NET provides strict type-safety"
"a five-years-old child"

for instance, what does type-safety mean? is it a noun? and how does it differ from "type safety" (without the - ).

[Tdol]

type-safety: the effect of the hyphen is to join the two together. It is a noun. The meaning isn't that clear to me, but I assume that it doesn't mean 'kind/sort', but refers to typing, so it must protect the text in some way.