What is the definition of the term 'crust' in geology?

The term 'crust' in geology refers to the surface and outermost layer of the Earth. It is the layer that we live on and constitutes the Earth's landmasses as well as the ocean floors. This solid crust is composed of a variety of rock types and is relatively thin compared to the layers beneath it, such as the mantle and the core. The crust is significant because it plays a crucial role in geological processes, including the formation of mountains, earthquakes, and volcanic activity, as well as providing a habitat for all terrestrial life. Understanding the crust's characteristics aids in comprehending broader geological concepts and processes.