The seven major lithospheric plates are the African plate, Antarctic plate, Eurasian plate, Indo-Australian plate, North American plate, South American plate and Pacific plate. These are also called Earth's tectonic plates, and there are actually more tectonic plates than just these seven, including several smaller microplates such as the Philippine plate in the Pacific Ocean. Some major earthquake-prone fault lines occur at the boundaries of these plates, such as the San Andreas Fault in California, which lies along the borders of the Pacific and North American plates.
Other hotspots for tectonic activity can be found at the boundaries of other plates that meet, such as the African and Eurasian plates. These two plates meet underneath the Atlantic Ocean, causing a massive underwater mountain range known as the Mid-Atlantic Ridge.
In addition to rubbing against each other and causing tectonic activity, the major lithospheric plates may also be subdivided in ways humans can't entirely detect. For example, according to the University of Texas, there is some evidence that the Indo-Australian, or Indian, plate may actually be two separate plates. The earth's plates have changed over time, and they are in a constant, though subtle, state of motion as the lithosphere floats on top of the earth's liquid core, and the plates will eventually look much different than they do today.