Shares outstanding are the number of shares out of the authorized shares that are issued to stockholders. Example:
Authorized Shs = 10,000,000 (meaning the Bd of Dir has authorized the potential issuance of that many shares)
Issued Shs = 5,000,000, which =s outstanding shares.
That leaves 5,000,000 authorized but unissued shares that can later be issued for various purposes.
One further distinction is Treasury Shares, which are authorized and issued shares, but are not outstanding. These shares are usually the result of the company repurchasing shares either on the open market or privately (such as from officers, etc.).

Market Capital =s the issued and outstanding shares multiplied by the current market price per share (pps).

Do a search for stock market terms and you will find all kinds of explanations of stock market terminology.

[This message has been edited by Wallace#1 (edited January 04, 2005).]