Precalculus is the level of mathematics between algebra and calculus. It's not an introduction to calculus, but rather a foundation for learning calculus. It generally covers relations and functions, periodic functions, and mathematical modeling. This may be enough math for some needs, or it can be preparation for continued study of mathematics.‎

If you learn precalculus, you can take more advanced levels of mathematics, starting with calculus. You can also be able to do more work with math and data than you would be able to without precalculus. It will expose you to mathematical thinking in order to apply mathematical formulas to data and modeling problems that you may come across. Learning precalculus can also get you ready for advanced studies in data science and computer programming.‎

Online courses can help you learn the foundations of precalculus and how it applies to commerce, engineering, and science. You can discover how studying the functions, applications, and properties of precalculus can help you use math as a tool to interpret, understand, and model everyday circumstances. Someone who wants to learn precalculus for data science may be interested in a course in algorithmic thinking, while another person who wants to take precalculus in order to do college-level math may prefer a course that covers a standard high-school precalculus curriculum.‎