Several planets orbit on the almost same plane around the Sun.
They are composed of Rocky planets (Mercury, Venus, Earth, Mars), Gas Giant(Jupiter, Saturn), Ice Giant(Uranus, Neptune).
Of course, there are also planets that go around fixed star other than the sun.
For example, 51-Pegasi-b is a planet which was discovered as a planet orbiting a star other than the sun for the first time.
This planet has half the mass of Jupiter, and it orbits very close to 51-Pegasi, 0.05au(7.5 million km). Therefore, the surface is considered to be heated to 1,000 ℃, and is called Hot Jupiter.
By the way, researchers at Kyoto University developed a multi purposed optical-infrared telescope in 2018. It has a 3.5m diameter, which is largest in Japan, and was named “Seimei”.
This telescope mainly is composed of three high technologys. First is a multi panel segmented mirror, Second is Mirror grinding process with extreme precision , and Third is the supporting mount that is able to quick slewing.
Researchers plan to use this telescope to explore new extra-solar planets.
In the near future, we human may discover planet where extraterrestrial creatures live.