Usually, most of the airlines offer particular classes - Economy, Business, and First Class.
Economy class: Available on all airlines, Economy-class is the least expensive travel option with the maximum area.
Business-class: Business class has additional space and legroom and offers in-flight meals. Business-class is more expensive than the Economy.
First-class: Usually placed closest to the aircraft front, First-class offers the most comfortable seats. First-class ticket holders have access to upgraded meals, shorter check-in line, and lounge. The fare of a First-class is the most expensive.