The Indian subcontinent is the peninsular region of South Asia, which includes India, Bangladesh, and Pakistan, usually also Sri Lanka, Nepal, Bhutan, and some disputed territory currently controlled by China, and sometimes Myanmar. Geographically, the region is bound by the Himalaya to the north and east, and the Arabian Sea and the Bay of Bengal to the south. The Hindu Kush mountains between Pakistan and Afghanistan/Iran are usually considered the westernmost edge of the subcontinent. It is also known as the Indo-Pak subcontinent, primarily in Pakistan. Being the only region in the world that is commonly described as a subcontinent, it is often simply called the Subcontinent, especially in Pakistan, because the use of India or Indian can sometimes offend non-Indian people in this region. The term South Asia is often used synonmously with the term Subcontinent, although technically South Asia refers more specifically to a political entity (the various countries that make up the Subcontinent), while the Subcontinent signifies a geographical area.
Geologically, this region is a subcontinent because it rests on a tectonic plate of its own, the India Plate, separate from the rest of Eurasia and was once a small continent before colliding with the Eurasian Plate and giving birth to the Himalayan range and the Tibetan plateau. Even now the India Plate continues to move northward with the result that the Himalaya are growing taller by a few centimeters each year. In addition, the region is also home to an astounding variety of geographical features that are typical of much larger continents, such as glaciers, rainforests, valleys, deserts, and grasslands in an area about half the size of the United States.