A high-rise is a tall building, as opposed to a low-rise building, and is defined differently in terms of height depending on the jurisdiction. High-rise buildings became possible to construct with the invention of the elevator and with less expensive, more abundant building materials. The materials used for the structural system of high-rise buildings are reinforced concrete and steel. Here are some key points about high-rise buildings:

• Definition: Various bodies have defined "high-rise" differently. For example, Emporis defines a high-rise as "A multi-story structure between 35–100 metres (115–328 ft) tall, or a building of unknown height from 12–39 floors." The New Shorter Oxford English Dictionary defines a high-rise as "a building having many storeys." In the U.S., the National Fire Protection Association defines a high-rise as being higher than 75 feet (23 m), or about seven stories.

• Occupied Floor: According to the International Building Code, a building is considered a high-rise when there is an “occupied floor” more than 75 feet above the lowest level of fire department vehicle access. The occupied floor, in this case, refers to the “occupied floor” of the highest story and not the level of the occupied roof.

• Materials: The materials used for high-rise buildings are reinforced concrete and steel. Most North American style skyscrapers have a steel frame, while residential blocks are usually constructed of concrete.

• Types: High-rise buildings can be used as apartment buildings, office buildings, hotels, or retail spaces. Sometimes, multiple purposes are combined. A residential high-rise building is also called a tower block or an "MDU", standing for "Multi Dwelling Unit." A very tall high-rise building is called a skyscraper.

• Height: There is no clear difference between a tower block and a skyscraper, but a building with fifty or more stories is generally considered a skyscraper. The opposite of high-rise is a low-rise building, and in the middle are mid-rise buildings.

High-rise buildings are more commonly found in urban or city areas where horizontal space is limited. They offer great views, especially on the higher floors, and often have a slew of amenities and events aimed at bringing people together. Mid-rise apartments usually offer more amenities than garden-style apartments and less walking than a garden-style apartment and less elevator waiting time than a high-rise. They also offer more privacy than a crowded high-rise and many mid-rise apartments offer more personal outdoor space than high rises.