A Line of Mountains
A chain of mountains, arranged in a line and connected by high ground, is called a mountain range. Mountains very rarely stand completely alone. Far more often they appear in these long, connected groups, with many peaks and valleys linked together across a region. Famous examples include the Himalayas, the Andes, and the Alps.
Why Mountains Form in Lines
Mountain ranges tend to be long and linear because of how they are made. Most of the great ranges on Earth were formed by plate tectonics — the slow movement of the giant slabs that make up the Earth's surface. When two of these plates push against each other, the crust along the boundary is crumpled and forced upward. Because that boundary is itself a long line, the mountains that rise from it also form a long line, which is why ranges stretch for hundreds or even thousands of kilometers.
Ranges, Belts, and Systems
Geographers use a few related terms. A single mountain range is one connected line of mountains. When several ranges with a shared origin sit together, they may be called a mountain belt or mountain system. The terms "mountain chain" and "mountain range" are often used to mean the same thing — a connected series of mountains standing together rather than alone.
Source
This article was written using information from Wikipedia.