A shelf liner is a useful addition in several situations. Wire shelves are great for garages and workspaces. They are economical, durable, and can handle a lot of weight. Unfortunately, wire shelves also have large gaps in their surface that allow small items to fall through. This can be a hassle, especially in a situation where things like screws, nuts, or other small hardware are prevalent.

Shelf liners can also be useful when you want to protect the surface of a shelf. An expensive or antique shelf with a brilliant finish deserves the added protection of an extra layer between its surface and whatever is to be stored on it.

Paper Shelf Liners
Inexpensive and incredibly simple, a paper shelf liner is the most basic variety. It can provide a buffer between a shelf and the stacks of china that are piled on it; it can also be used to wrap presents. The actual protection provided by a paper shelf liner runs pretty thin (it's paper!), but it will prevent items from scratching a surface or getting stuck to it. Paper liners are sometimes difficult to keep in place. They may also allow moisture to seep through or around them.

Rubber Shelf Liners
These shelf liners are a large step above paper. They are often ribbed which helps them stay in place and makes them easier to cut to the desired size. Their resilient quality provides an excellent cushion that can protect the surface of the shelf as well as items like fine crystal or china. The ridges in the surface also help them stay in place without the use of adhesives. Rubber shelf liners are often porous. They might not be the best choice to protect shelving from moisture. Also, the ribbing can make some models difficult to clean.

Padded Shelf Liners
Much like their rubber brethren, padded liners can stay in place on their own. They provide excellent protection both for the surface beneath them and the items above them, as well. Look for models made of non-porous polyethylene to use in moisture-rich areas.

Vinyl Shelf Liners
Though there are some thin vinyl shelf liners that are made for protecting the surface finish of fine wood, their performance is very similar to that of a rubber or padded liner.

Vinyl truly shines in tough jobs. A vinyl shelf liner is the one you want in the garage to lay over your wire shelving. It is thick, easy to clean, and will fill in those gaps so you don't loose any nails or spark plugs. Vinyl is, itself, a very strong material, and adding it to a shelf of steel wire makes it even stronger. It can also bring some extra protection to a metal shelf in the form of water resistance.

A thick vinyl shelf liner will not be able to be cut with a pair of scissors. Many companies that sell wire shelves will also sell vinyl shelf liners that are designed specifically for their products.