Beta: A measure of the volatility, or systematic risk, of a security or a portfolio in comparison to the market as a whole.
Market Cap: The total dollar market value of all of a company's outstanding shares.
P/E Ratio: A valuation ratio of a company's current share price compared to its per-share earnings.
Profit Margin: Profit margin measures how much out of every dollar of sales a company actually keeps in earnings. Profit margin is very useful when comparing companies in similar industries.
Ticker Symbol: A series of letters representing a particular security listed on an exchange or otherwise traded publicly.
Definitions from Investopedia.com
Researchers and investors can get a good picture of where a public company has been and where it is heading in filings available from the U.S. Securities and Exchange Commission (SEC). These forms may be filed annually, quarterly, or periodically as required by the law.
Investopedia describes some of the most common forms: