They vary dramatically in quality (similar to high schools) and they are typically two-year colleges. For training mid-skill workers, they do a decent job. It is hard to really compare them to four-year colleges because they have open enrollment (anyone can go regardless of previous grades).

They also provide an affordable way of transitioning to a four-year college for the highly motivated and in some states, top-ranking high school students can enroll in community college to earn an associates degree their high school pays for putting them on an accelerated path.