Final answer:
Most exoplanets discovered thus far are located very close to their parent stars, some of which are massive 'hot Jupiters.' Detection methods are biased towards larger planets near their stars, although small rocky planets like Earth are also common in our galaxy.
Step-by-step explanation:
Most of the exoplanets detected to date are found very close to their parent star. An example of this type of exoplanet is the widely known class termed 'hot Jupiters,' which are massive planets that orbit close to their stars. This is a distinct characteristic from the attributes of gas giant planets in our own solar system. Moreover, many exoplanets are in eccentric orbits, suggesting that giant planets can migrate inward from where they were formed. While small rocky planets, similar to Earth, are also common in the Milky Way Galaxy, our current detection methods have been initially more successful at finding larger planets near their stars due to the detectable gravitational pull or transit effects these exoplanets have on their stars.