Who invented the telescope?
The earliest evidence of telescopes were refracting telescopes from the Netherlands in 1608. Their development is credited to three individuals: Hans Lippershey and Zacharias Janssen, who were spectacle makers in Middelburg, and Jacob Metius of Alkmaar.
Hans Lippershey invented the telescope, sometime before 1608 A.D. (which is the earliest record of him applying for a patent). Jacob Metius applied for a similar patent only a few weeks later.
Galileo greatly improved upon these designs the following year, using improved optics. He did not invent the telescope, but he was both the first person to use it and also improve the telescope. It was the astronomical observations recorded by Galileo in 1610 (including the discovery that Jupiter has moons of its own) that is most closely associated with the first use of the telescope.