There are a variety of calculators available. Some are very specialized, some quite simple. There are calculators that can only do simple arithmetic, and ones that can find a single point on a parabola. Prices increase with complexity, so determining the correct calculator can save money and aggravation.

**Basic Calculators**

Basic calculators are used for simple functions. Generally less than ten dollars, basic calculators add, subtract, multiply, and divide. Some include a simple memory function, larger display, large sized keys or a see-through design to use with overhead projectors. Basic calculators are for simple arithmetic. They are powered by either batteries or a small solar cell.

**Printing Calculators**

Most printing calculators are designed for use in bookkeeping and accounting. They contain all the keys of a basic calculator, with additional keys that allow for easily finding percent, subtotal, grand total, tax rate, and a number of other functions used when totaling large quantities. The print ability allows the user to check for common entry errors like transposed or skipped digits, use the printout as a receipt or to not print. Most also include a rounding function and way to choose the number of decimal places. how to work out a percentage

A top-of-the-line printing calculator can cost more than $100, though they can be found for less. Printing calculators are available as battery operated portable models, though most require access to an electrical outlet.

**Scientific Calculators**

Scientific calculators are most often used by students. They are used to solve mathematical, physics or chemistry problems. They are also often approved for use in standardized tests. These calculators may include multifunction buttons for a smaller, full featured tool. They are able to calculate root values, with separate buttons for square, cube, and any root. They also have trigonometric, logarithmic and exponential function keys.

Most have a single line display, but some are available with an expanded display. Aimed primarily at students, these calculators can cost as little as $10. More expensive scientific calculators usually support more functions, provide larger memory, or allow problems to be keyed in exactly as they appear in a textbook.

**Business and Financial Calculators**

Financial and business calculators are designed to be used mainly in calculating business-related equations, for students studying business calculus, and for tracking or plotting financial information. Financial calculators can build amortization tables for loan payments, determine APR, estimate compound interest, total paid, interest paid and other functions of money over time.

Business calculators include more prominent placement of the most common functions used in business calculus or math. They often include advanced statistical models and analysis functions. More expensive models include larger memory, more cash flows, and more functions.