Travel hacking is not some elaborate way to hack a computer or something like that. It is simply using the tools from airlines, hotels, and banks to travel for free.
The simple answer is racking up miles and points and redeeming them for free flights, and hotel stays.
Pick an airline or hotel brand you think you will be loyal to. By doing this, you can create miles and points for these programs.
Airlines have joined forces to help each other out. These are called Alliances. Star Alliance would be associated with United, Singapore Airlines, and Air Canada.
Travel credit cards are by far the easiest way to earn lots of miles and points to achieve free travel.