Airlines firsts that changed the industry

In 2010, commercial airline industry revenues topped $554 billion and are forecast to hit $598 billion in 2011, according to the International Air Transport Association. The growth over the last 108 years has been enormous, and so have the changes. Some were born of necessity, others of ingenuity, but many left an indelible mark on air travel.

Here, we take a look at some of those changes: the good, the bad and the inbetween - they're all "firsts" that changed the industry.