MathForAll is a course that is designed to cover those topics in mathematics that are most commonly used in applied mathematics at various levels. Having personally seen students struggle with such concepts has inspired me to help them out being creating content that can enlighten them to these concept in the simplest way possible. The course is well structured and offers a chance to test oneself at the end and also includes graphical content. This course on Functions is designed in a simple way that will help students, especially those that are studying for their GCSEs or IGCSEs, get a grip on the important concept of functions in a very efficient way in terms of time and finances. The course covers functions keeping in mind real life examples, while highlighting ways in which real life examples can be expressed mathematically. Equipped with an introductory video, practical videos with problem solving examples and a practice exercise at the end, this course offers an excellent opportunity to learn how to deal with a commonly used concept. The course covers, relations, functions, examples of functions, special functions, modulus functions, range and domain, composite functions and inverse functions, with concepts and examples often being shown in short videos.