Choose a paint sample based on the intended application. Using a paint sample lets a painter know how the finished product will look in a variety of lighting conditions.
Use flat or eggshell paints for indoor areas that don't experience a lot of wear and tear, such as bedrooms or hallways. Flat paints hide surface imperfections best. Glossy paints are ideal for areas with high traffic and areas with a lot of moisture, such as baseboards, kitchen walls and bathrooms.
When painting outside, always use exterior paint. It is designed to hold up against rain and snow. Do not use exterior paint indoors because the anti-fungal agents in exterior paint are not approved for indoor use.