Earthquakes are caused due to the collision of tectonic plates.

Explanation:

Tectonic Plates:
Tectonic plates are large pieces of the Earth's lithosphere that fit together like a puzzle. These plates are constantly moving, albeit very slowly, due to the convective currents in the asthenosphere beneath them. There are several major tectonic plates, such as the Eurasian Plate, North American Plate, Pacific Plate, etc.

Plate Boundaries:
The boundaries where tectonic plates interact are known as plate boundaries. There are three main types of plate boundaries:

1. Convergent Boundaries: At convergent boundaries, two plates collide with each other. There are three subtypes of convergent boundaries:
- Continent-Continent Collision: When two continental plates collide, they can't sink beneath each other due to their buoyancy. Instead, the collision leads to the formation of mountains, such as the Himalayas.
- Continent-Oceanic Plate Collision: When a continental plate and an oceanic plate collide, the denser oceanic plate is forced beneath the lighter continental plate in a process called subduction. This subduction can result in the formation of volcanic arcs, like the Andes.
- Oceanic-Oceanic Plate Collision: When two oceanic plates collide, one of them is usually subducted beneath the other. This can lead to the formation of island arcs, such as the Japanese archipelago.

2. Divergent Boundaries: At divergent boundaries, two plates move away from each other. As they separate, magma rises from the asthenosphere and fills the gap, creating new crust. This process is known as seafloor spreading. The Mid-Atlantic Ridge is an example of a divergent boundary.

3. Transform Boundaries: At transform boundaries, two plates slide past each other horizontally. This movement can result in earthquakes, but it does not create or destroy crust.

Earthquakes and Tectonic Plates:
Earthquakes occur when stress builds up along the boundaries between tectonic plates. As the plates try to move past each other, the accumulated stress is suddenly released, causing seismic waves to ripple through the Earth. These seismic waves are what we feel as an earthquake.

Most earthquakes occur at plate boundaries, especially along convergent and transform boundaries. However, earthquakes can also occur within plates, although they are less common in these areas.

In conclusion, earthquakes are primarily caused by the collision of tectonic plates along plate boundaries. This collision creates stress, which is released in the form of seismic waves, resulting in an earthquake.