Hewlett Packard offers three main types of calculators: scientific, financial, and graphing. For students in middle school, scientific calculators are the most popular, as they provide basic arithmetic functions and many more advanced computations. Graphing and financial calculators provide the additional computational power required by students in high schools and colleges, as well as professionals.

In addition to arithmetic functions, all HP calculators include trigonometric, logarithmic, exponential, and power functions. These functions form the core of the math courses through which students progress, making HP calculators valuable tools. In addition, some HP calculators incorporate statistical functions such as sums, means, and standard deviations. Some HP calculators also include Reverse Polish Notation, a data entry format that reduces the number of necessary keystrokes.

When scientific calculators don't provide you with the computational power that you need, graphing calculators are the next step. These provide users with a larger screen on which you can view equations and edit them. In addition to being able to graph equations in Cartesian and polar coordinates, these HP calculators have thousands of built-in functions. Even better, with the built-in memory of HP graphing calculators, users can write their own programs to solve problems and automate repeated calculations.

HP financial calculators are used by both students and professionals, and include specialized financial functions. Options are immediately available to calculate loan payments, interest rates, net present value, and annuities. In addition to being used by bank officers and actuaries, these calculators are also approved for use on professional examinations such as Certified Financial Planner (CFP) and Chartered Financial Analyst (CFA) exams.