What is the difference between a terrestrial planet and a gas giant

Gas Giants are usually bigger than Terrestrial Planets. Gas Giants also have thicker atmospheres, and have gaseous surfaces. Terrestrial planet tend to be smaller, and have solid surfaces. In our solar system, Mercury, Venus, Earth (home), and Mars are Terrestrial planets.  While Jupiter, Saturn, Uranus (the planet), and Neptune are Gas Giants. Gas Giants are also known as Jovian planets.