I am not going to try to explain any of these myself, becaue I would probably botch it.  2 of my favorite sites for learning about these types of things are Investopedia.com and Yahoo!Finance.  They both have excellent glossaries that can give decent explanations of what these terms and ratios mean.  One thing that I have learned since I started researching stocks a couple of years ago is that these numbers and ratios can vary between different industry groups, so it may be beneficial to compare them to industry specific averages rather than look for an absolute numbe.  For example a company with a P/E (price to earnings ratio) of 25 may still  be a good buy if the industry average is much higher than that, as long as the other fundamentals are good.  Another good resource is Investor's Business Daily, which has established many criteria to look for in leading stocks based on fundamental analysis.