I've read a rather heated discussion over the term backpacking in Lonely Planet website. It's funny how some people argue over the "rules" of "proper" backpacking. A lot of people give a narrow meaning to the word and define it as camping, hiking, mountaineering or any travel to the wilderness.
For me backpacking simply means a form of low-cost travel or budget-travel often with the use of backpack.Low-cost or budget is subjective therefore one should not give an air-tight definition of the term backpacking.
The factors that differentiate backpacking to traditional tourism are:
- use of public transport as a means of travel
- use of hostel, inns, pension houses or any cheaper accommodations than any traditional hotel
- preference on the use of backpack
Hope I was able to show you some light regarding backpacking. :)