Most American colleges require their students to earn a certain number of college credits  in order to qualify for a degree (or to satisfy core curriculum or major requirements).

The typical college education leading to a bachelor degree runs for four years. Each year divides into two semesters, fall and spring. Students either take the summer off or enroll in credit-bearing courses during the summer to make up for failed work or to accelerate their progress.

Since many colleges require 128 credits to graduate, this number gives a good overview of the system. This computes to 16 credits per semester or 32 per college year. An individual college course could be two, three, four, or more credits depending on the number of hours of instruction per week. A common semester configuration would involve four courses of four credits each. To earn the credits, in addition to attending the class with some regularity, the student might have to write research papers, pass examinations, or both.

In some colleges, students can earn credits by doing independent study projects that do not require class attendance. In many cases, students can also earn credits based on their performance on standardized advanced placement examinations. Some colleges also award a limited number of credits to older students based on life experience.

A key fact about the American college credit system is that it tends to compartmentalize the process. American students take their courses on a one-by-one basis and rarely have to worry about the types of standardized qualifying examinations students in many other countries take in order to earn their degrees.

Credits may or may not be transferrable between colleges, depending on the requirements of the colleges involved.