The A300 was the first twin-engined widebody airliner in the world. It inspired Boeing twins such as Boeing 767 and 777 and paved the way for ETOPS flights.
Taking on the major aircraft manufacturers 30 years ago required more than nerve, it required a new approach to the market. Although the consortium partners of Airbus were well known in aviation circles, Airbus itself was an unknown entity.

Airbus listened to the passengers' and operators' demands. There was a niche to be filled: a short-to medium-range aircraft that had the operating economics of a twin-engined aircraft and the ability to carry 250 to 300 passengers in comfort. The selling price should also be lower than any competitor.

Airbus partners employed the latest technology, some derived from the Concorde. On entry into service, in 1974, the A300, was very advanced and influenced later subsonic airliner designs. The technological highlights include:

- Advanced wings by De Havilland (later BAE Systems) with:
- supercritical airfoil section for excellent economical performance
- advanced aerodynamically efficient flight controls
- advanced 222-inch diameter circular fuselage section for 8-abreast passenger seating and wide enough for 2 LD3 cargo containers side-by-side giving it bigger belly cargo cross-section than a Boeing 747. The circular fuselage crossection was later used in Boeing 777.
- Structures made metal billets, reducing weight
- High degree of automation, requiring the flight engineer's intervention only in emergency
- the first airliner to be fitted with windshear protection
- advanced autopilots capable of flying the aircraft from climb-out to landing
- fully electronically controlled brake-by-wire braking system

Later A300s incorporate other advanced features such as

- 2-man crew by automating the flight engineer's fuctions, an industry first (a request made by Garuda Indonesia, an idea proposed by Bacharuddin Jusuf Habibie, which at that time was Indonesia's Minister of Research and Technology)
- glass cockpit flight instruments
- extensive use of composites
- centre-of-gravity control by shifting around fuel
- the first airliner to use winglets for better aerodynamics

All these made the A300 a perfect sustitute for the widebody trijets such as McDonnell Douglas DC-10 and Lockheed Tristar for short to medium routes. On the early versions, Airbus even used the same engines and similar major systems as the DC-10. Asian airlines bought the concept and used the early A300s as a complement to the widebody trijets on such routes.

After the launch, sales of the A300 were weak for some years, with most orders going to airlines that had an obligation to order the locally-made product - notably Air France and Lufthansa. At one stage, Airbus had 16 "whitetail" A300s - completed but unsold aircraft - sitting on the tarmac.

In 1977 giant US carrier Eastern Airlines leased four A300s as an in-service trial, and then ordered 23 of the type. From then on, the A300 family sold well, eventually reaching the current total of 843 on order or delivered.

Also, Olympic Airways operated A300-B4 and A300-605R jets for several years. Now it only operates a single A300-605R (SX-BEM 'Creta') (as of February 2005)

It found favour in particular, with Asian airlines. It was snapped up by Japan Air System, Thai Airlines International, Singapore Airlines, Malaysia Airlines, Garuda, China Airlines, PIA, Indian Airlines, Trans Australia Airlines and many others. As Asia is not restricted by the FAA 60-minutes ruling for twin-engine airliner, Asian airlines used A300s for routes across Bay of Bengal and South China Sea. The Australians used them for domestic transcontinental routes. By 1981, Airbus was growing rapidly, with over 300 aircraft sold and options for 200 more planes for over forty airlines. This fact was not lost to Boeing which responded with the Boeing 767.

The A300 provided Airbus the experience of manufacturing and selling airliners competitively. The basic fuselage of the A300 was later streched (A330 and A340), shrunk (A310), or modified into many derivatives (Airbus Beluga).

Currently, the A300 is reaching the end of its market life and is now mainly sold as a dedicated freighter. The current version is the A300-600R and is rated for 180-min ETOPS.

The A300 has enjoyed renewed interest in the secondhand market for conversion to freighters.