The world's biggest airshow is celebrating its 50th anniversary this year. The , which kicked off this week, has already seen Airbus and Boeing announce multi-billion dollar orders for their new aircraft.

Airbus has been out touting its next generation plane, the A350, while has been displaying its 787 Dreamliner, after the company fixed recent battery problems.

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Click ahead for a look at the highlights from the show.

By CNBC's Deep Bagchee, follow him on @DeepBagchee

Airbus's new A350 is built largely from lightweight composite materials, and has two ultra-quiet Rolls-Royce engines. The twin-aisle plane, also known as a , made its , ahead of the airshow.

It will compete with Boeing's 777 (which is older and heavier) as well as the 787 Dreamliner, which is also made from carbon-composite materials.

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The A350 will come in three variants (the 800, 900 and 1000) and will carry between 250 and 350 people, more than its Boeing competitor. However, Boeing has just announced it will build a longer version of the 787, called the 787-10, which will carry up to 350 passengers. The first test flight of that aircraft is expected in 2017.

Boeing's 787 Dreamliner has been a mainstay of airshows in recent years. The plane, which made its first flight in December 2009, was revolutionary in its extensive use of light-weight composite materials, improving passenger comfort and fuel efficiency.

The plane was grounded by the U.S. aviation regulator, the FAA, after overheating batteries raised alarms. But Boeing says it's now confident in the fix and the planes are back in the air.

Speaking at the airshow, that the Dreamliner had actually exceeded its targets for fuel efficiency. The Dreamliner is the fastest-selling plane in history with 677 orders by its roll-out in 2007.

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Unmaned Aerial Vehicles (UAVs), popularly known as drones, have also been a big feature of the Paris Airshow.

This Falco drone is made by Selex, a unit of Italian manufacturer , and can fly continuously for up to 14 hours.

Finmeccanica is one of four European defense companies that called this week for a , in order to build a medium-altitude long-distance vehicle.

State-owned Air India, which has faced a series of financial and labor problems in recent years, displayed its new 787 aircraft at the Paris airshow. The airline just took delivery of its seventh plane, and will receive 14 of the 27 Dreamliners it has ordered by the end of this year.

The airline, which has used the 787 to fly the Paris-to-Delhi and London-to-Delhi routes, was forced to ground the planes recently because of the FAA order to ground all Dreamliners.

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British Airways's first A380 took part in a flying display at the Paris Airshow. The airline has set July 5 as the date for its first flight, according to Australian Business Traveller magazine.

The super jumbo aircraft, which can accommodate up to 469 passengers, will begin London-to-Los Angeles flights in the Autumn.

The airline will also take delivery of its first Boeing Dreamliners later this month, boosting its aging fleet.

Europe's new military transport aircraft, the A400M, was part of the flying display at the airshow. The Airbus-made aircraft has four engines, and can carry heavy payloads, including military vehicles and helicopters.

The plane will greatly improve the ability of European nations to airlift troops and equipment to troublespots, and was aimed at bridging a gap in the region's military capabilities. In recent years for example, Europe has relied on U.S. aircrafts to airlift troops to Afghanistan, and even France used U.S. planes to transport troops and equipment to Mali in January this year.

Qatar Airways has just taken delivery of its seventh Dreamliner aircraft. Qatar Airways was voted the world's best airline last year, but lost the top spot to Emirates at this year's World Airline Awards.

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Qatar Airways uses the Dreamliner for its London-to-Doha route. Each passenger in Qatar's 787 business class cabin has an aisle seat, in a 1-2-1 configuration. The airline also offers passengers in-cabin wi-fi.

Russia's Sukhoi displayed its latest Su-35 aircraft at the Paris Airshow, which is a more modern variant of the Su-29 and Su-30 used by the Chinese and Indian airforces. The fighter jet is highly maneuverable because of "thrust-vectoring", which means it uses exhausts that can move and push the plane in a particular direction.

Sukhoi is hoping to find new customers for the Su-35, especially from emerging markets.

Canada's , a maker of regional and executive jets, is hoping to find lots of new customers for its next-generation CSeries aircraft. The plane, which is Bombardier's largest, can seat 130 passengers, making it a competitor to the Boeing 737 and Airbus A320.

The CSeries is more fuel-efficient than other regional jets currently in the market. Bombardier's biggest competitor is Brazil's , which makes the popular 190 jet.

The CSeries, which cost $3.3 billion to develop, was delayed last year after supplier problems. However, Bombardier said the problems have now been fixed, and that it is bullish on opportunities in BRIC nations (Brazil, Russia, India and China).

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