Differences and use cases of "net", "network", "mesh", "grid"

What are the differences between net, network, mesh and grid?

If I have a look at the OED entries, I have a feeling of rather a circular definition:

mesh Material made of a network of wire or thread...

net A piece of open-meshed material...

grid A network of lines that cross each other...

Could you list some most common collocations with each of the words and explain why this particular one is used? Such as why do we use mosquito net and not mosquito mesh?

Solution 1:

The difference lies partly in the physical properties of the different nouns, and partly in their intended use.

A mesh is what all these terms have in common; it's a weaving of some thread-like substance into a regular-polygonal pattern (typically the polygons are squares, but not necessarily). The polygons are generally expected to all have equal size, and any type of weaving involving non-polygonal patterns - a knitted sweater for example - is not considered a mesh. A window screen for keeping insects away is a good example of a mesh; a metal chain-link fence is a good example of one not based on squares.

A grid is a mesh that's flat - for example, U.S. city streets are usually organized in a square mesh pattern, but we call this pattern a grid because it's basically flat (the earth it lies on is flat).

A net is a mesh that is not necessarily flat; it's made of flexible material. Thus, fishing nets can be wrapped into a bag-like shape for hauling in fish. This also explains, as you asked, why we say mosquito net and not mosquito mesh - although mesh could be sort of appropriate if we're talking about a fixed mesh (like the wall of a tent), intended to keep mosquitos out but not intended to be used for catching them (as a net would be used).

(So in general: we say net if we're talking about a mesh whose purpose is to capture, contain, or exclude something.)

Finally, a network has the least in common with the above three because it doesn't necessarily follow a regular pattern. Network never refers to any of the above terms; it refers to irregularly patterned systems of connection. Computer networks, for example, contain many connected computers, but their physical proximity to one another is completely arbitrary.