Question

What is meant by galaxy and how many galaxy are there ?

Answer 1

Galaxy is a huge collection of dust , stars, gas , and their solar system. There are about 100million of galaxy in the universe

Answer 2

A galaxy is a gravitationally bound system of stars, stellar remnants, interstellar gas, dust, and dark matter. The word galaxy is derived from the Greek galaxias, literally "milky", a reference to the Milky Way

All in all, Hubble reveals an estimated 100 billion galaxies in the universe or so, but this number is likely to increase to about 200 billion as telescope technology in space improves