The Olympus 52mm Protective Filter is a wise initial investment.
It is the standard Protection filter most people are familiar with. It can help protect your valuable investment from dust, moisture and scratches, which can lead to costly repairs. A Protective filter is probably the most popular filter people use. As a lens protector, it should be left on at all times to guard against front element damage but also adds the benefit of rendering your images clearer.
A Protective filter is also the best available protection against accidental damage to the front element of your lens. A lens that accidentally gets dropped on its front element while hiking can potentially be saved by purchasing this item. Some people refer to it as "cheap insurance".
The multi-coated surface minimizes reflection at the filter surface which reduces flare and ghosting.