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.
Placing trades can feel overwhelming if you donât understand the importance of calculating margin. A margin allows you to buy securities by borrowing money. The margin is the difference between the market value of a stock and the loan amount. Check out the sections below to see how TD offers helpful tips to understand margin calculations so you can better predict profits and losses and become a more confident, skilled investor.