After booking a private jet charter, you might be interested in the type of jets available to you for your travel. Generally, jet charter companies have one of two types: the General Dynamics Gulfstream or a Gates Lear Jet. While jets usually had four engines in decades past, the jets of today usually have only two. Advances in engine technology have allowed jets to become increasingly lighter and more gas efficient to fly. With over eleven thousand business jets operating worldwide, renting a private jet is an active business for people who like to travel efficently.