A file extension is the characters after the last dot in a file name. For example, in the file name winmail.dat, the file extension is dat. It helps Windows select the right program to open the file.
Margin is borrowing money from your broker to buy a stock and using your investment as collateral. Investors generally use margin to increase their purchasing power so that they can own more stock without fully paying for it.But margin exposes investors to the potential for higher losses.ut if you bought the stock on margin  paying $25 in cash and borrowing $25 from your broker  you'll earn a 100 percent return on the money you invested. Of course, you'll still owe your firm $25 plus interest.
The margin is the client's equity in the value of the portfolio or trading position. The client's trading limit is set at a multiple of the margin deposit. Margins can be in the form of cash and/or shares. However, margin shares must be on our list of marginable stocks.