Introduction to physics varies significantly between high school and undergraduate levels, with three main types of courses available. High school courses may align with university introductory physics, but they can also be more basic, depending on the curriculum. Undergraduate courses often incorporate calculus, especially when using textbooks like Halliday/Resnick/Walker's Fundamentals of Physics. Some universities offer physics courses with minimal math, which can lead to confusion about the depth of understanding required. Overall, mastering a calculus-based textbook like Halliday suggests a strong foundation in physics, comparable to that of an undergraduate student.