The Forex Training Guide

In the stock market, this rule applies to the nth degree, as you are investing your own money in what could be considered a high risk wager, and you are playing with fire if you do not have at least a general background knowledge of how it functions. Since having a background in any area is helpful in guiding you down a path in that particular region, the more solid your basis of investment knowledge is, the more likely you are to profit from any attempt to trade on the open market.
In many ways, trading on the stock market can be compared to driving – you do not have to be an expert to get behind the wheel of a car, though you are expected to have some previous knowledge about basic traffic laws, including moving violations, safety regulations, and other legal vehicular infractions, which are learned through either specific study and coursework or even through some form of simple exposure (such as the years you have spent riding with your parents and others who have driven for years). You should be able to comprehend the basic tools used to navigate a car (where the break pedal is located versus the gas, and how to use the rearview mirror, for example), even if you have never touched a steering wheel.