Bootstrapping is the process of funding your own startup, and unless you're already a multi-millionaire with money to blow, that's going to necessitate being very strategic about where your venture spends its money. Another option that many people don't consider is keeping your current job while launching your company so that you have a steady stream of personal revenue and (hopefully) money for personal investment into the venture.
I won't use this page to give you strategies on keeping your costs low, since there are ample writings about that from people with a lot more experience to share. Instead, we'll talk about the upsides and downsides of bootstrapping, and where it might be most applicable.
When you bootstrap, the resulting company is entirely yours. This has a few implications:
The most obvious drawback of bootstrapping is that it involves more personal risk than a venture with significant fundraising. If the whole thing goes kaput, that's your money that has been burnt through. If a venture requires a lot of capital, bootstrapping may simply not be feasible.
Like any other type of funding, bootstrapping is neither good nor bad, simply better-suited for certain projects and certain entrepreneurs. We won't cover any more funding methods in detail, but I encourage you to spend ample time thinking about what will fit you best.