Note. Unity 5 introduced the Standard Shader which replaces these shaders.
Reflective shaders will allow you to use a Cubemap which will be reflected on your mesh. You can also define areas of more or less reflectivity on your object through the alpha channel of the Base texture. High reflectivity is a great effect for glosses, oils, chrome, etc. Low reflectivity can add effect for metals, liquid surfaces, or video monitors.
One Base texture with alpha channel for defining reflective areas
One Reflection Cubemap for Reflection Map
One Normal mapA type of Bump Map texture that allows you to add surface detail such as bumps, grooves, and scratches to a model which catch the light as if they are represented by real geometry. See in Glossary, no alpha channel required