1. (sometimes capital) new, recent, or a new or modern form or development: neoclassicism; neocolonialism. 2. (Geological Science) (usually capital) the most recent subdivision of a geological period: Neogene. [from Greek neos new]. Also, esp. before a vowel, ne-.
Although optical telescopes are the type most commonly used for stargazing and amateur astronomy, lots of astronomical research is done on telescopes that look at other wavelengths of light. Each of these wavelength ranges shows us something unique about the universe and allows us to view events and objects that can't be seen with human eyes.
The visible spectrum of light includes all of the colors that can be detected by the human eye, and it only makes up a very small portion of the total electromagnetic spectrum, about 400nm to 700nm. Optical telescopes use polished mirrors or glass lenses to focus visible light as it comes in through the aperture. There are two main types of optical telescopes, reflectors and refractors. Reflecting telescopes tend to be much larger and use parabolic mirrors to focus light. Refracting telescopes use lenses to bend light as it passes throught them. These are limited by the size of the lenses, and therefore tend to be much smaller than reflectors. Radio telescopes are used to study much longer wavelengths than visible light. Often, radio telescopes use a dish to focus the radio waves onto the receiver. The receiver then sends the signal to be recorded for astronomers to study.