Telescope Basics

(This is a work in progress)

An optical telescope is an instrument designed to gather and focus light. It does this through the use of lenses, mirrors, or a combination of the two. Other kinds of telescopes exist to gather energy from other parts of the electromagnetic spectrum, including infrared, ultraviolet, radio, microwave, x-ray, and gamma ray energy. However, this wiki is primarily concerned with light, so unless otherwise stated, our discussion will be about light.