A telescope is a device used to observe distant objects by their emission, absorption, or reflection of electromagnetic radiation. Originally meaning only an optical instrument using lenses, curved mirrors, or a combination of both to observe distant objects, the word telescope now refers to a wide range of instruments capable of detecting different regions of the electromagnetic spectrum, and in some cases other types of detectors. Hoysaleshwara Temple, Halebidu, Karnataka you will be astounded by many of the carvings. One such carving is of a person holding a gadget to the eye & looking skywards which means they had a device for looking at the sky. The carvings 1 in a 900 years old. The first known practical telescopes were refracting telescopes with glass lenses and were invented in the Netherlands at the beginning of the 17th century. They were used for both terrestrial applications and astronomy.