An airship (also known as a dirigible) is a "lighter air aircraft" that can be steered and propelled through the air using rudders and propellers or other plunge. Unlike other aerodynamic aircraft such as fixed-wing aircraft and helicopters, which produce lift by moving a wing, aerostatic aircraft, such as airships and hot air balloons, stay aloft by filling a large cavity.

The airship is one of the oldest vehicles for airborne operations. After the appearance of the airplane, and a series of disasters, the airship lost its demand and its use in the modern aviation era has been limited. This may be changing. The airships have ability to drift and lift heavy loads over long periods of time with very low fuel utilization due to this advantage it has renewed the interest in these vehicles as possible aerial platforms.

An airship is different from an airplane or a helicopter because they do not use lift in order to get off the ground. Instead, they fill a large hollow space with lifting gas, such as helium or hot air and this makes the ship lighter than air so it will be lifted off the ground. The first controlled powered flight in history was succeeded with an airship.

There cannot be a more effective outdoor medium than the airships. There are number of research and studies that prove the effectiveness of the airships. Around the world the airships are appearing more and more dressed up in different catchy colors and companies are increasingly using them for promotion and advertising.

Recent research has considered using long survival, high altitude airships as less expensive substitutes for communication satellite operations, wherein the design was done in conjunction with the design of the airframe. Furthermore, there are different types of airships, which are as briefly described below:

Rigid airships

Rigid airships were used in the beginning of the century. They suffered a lot due to the routine accidents. The rigid airships have a definite structure or a complete framework with a partial keel, to help the airbag to maintain the shape

Semi rigid airships

The semi-rigid airships are smaller than the rigid airships and have only a fixed keel as an internal support.

Non-rigid airships

Non-rigid airships are also known as blimps and they are airship with no rigid internal supporting structure and no keel to support and maintain the shape of the airship. They rely on pressure of lifting gas usually helium and strength of the airbag to maintain its shape.

Metal clad airships

Metal-clad airships were of two kinds: rigid and non-rigid. Each kind used a thin gastight metal envelope, rather than the usual rubber-coated fabric envelope. Only four metal-clad ships are known to have been built, and only two actually flew: Schwarz's first aluminum rigid airship of 1893 collapsed, while his second flew, the non-rigid ZMC-2 flew 1929 to 1941, while the 1929 non-rigid Slate "City of Glendale" collapsed on its first flight attempt.

Blimps are quite similar to moored balloons. The main characteristics that make them similar are their shape, but moored balloons have no impulsion, whereas blimps are free flying aircrafts, which able to determine the direction in which they are heading.

There can be various uses of blimps. For example, advertisement is used through blimps because it provides large space where advertisements can be placed. The other use is surveillance because it makes little noise. Lastly, blimps are used for research because they allow a long time of flight for observation.