Mechanical Turk is Amazon's take on micro-jobs. These are small miniscule-jobs that you can do for other people, which they call HITs, or Human Intelligence Tasks. These are super simple tasks that anyone can do. Some examples are listing off some URLs with certain kinds of images for one cent, or recording a few phrases with a microphone for 6 cents.
A stock normally represents your ownership within the corporation. The advantage of holding a stock is that not only do you own a piece of the company, you also have the liberty to trade these instruments in an open market (and thus realize capital gains) and reap income in the form of dividends, which are declared when the company makes profits. Stocks, as an investment class, are very volatile and may be subject to sharp market fluctuations and uncertainty.
Before I talk about some of the methods for making money online, I wanted to address the role of pain versus pleasure. Every decision that we make in life is weighed on a pain-versus-pleasure scale. We will always do more to avoid pain than we will to gain pleasure, plain and simple. However, this is also what holds us back from succeeding in any endeavor.