Margins can refer to different things depending on the context. Here are some definitions of margins from various sources:

1. Finance: In finance, margin is the collateral that an investor has to deposit with their broker or exchange to cover the credit risk the holder poses for the broker or the exchange. Margin can also refer to the money borrowed from a broker to purchase an investment and is the difference between the total value of an investment and the loan amount).

2. Business: In the business world, margin is the difference between the price at which a product is sold and the costs associated with making or selling the product (or cost of goods sold). Broadly speaking, a company’s margin is its ratio of profit to revenue. Margin is one of the most important performance metrics for businesses to track.

3. Economics: In economics, thinking at the margin means to think about your next step forward. The word “marginal” means “additional.” Marginal cost refers to what a seller or producer has to sacrifice in order to sell or produce one more item. Opportunity cost refers to what you have to sacrifice–at the margin–as a buyer because when you buy one thing you can’t buy something else.

4. Printing: In printing, margin refers to the part of a page or sheet outside the main body of printed or written matter.

In summary, margins can refer to collateral in finance, the difference between revenue and expenses in business, the concept of thinking at the margin in economics, or the part of a page outside the main body of printed or written matter in printing.