are courses numbered 100+ hard courses?

Colleges and Universities A-Z University of California - Berkeley
1

<p>I remember them saying at calso that you shouldnt take upper division courses (which i think are courses numbered above 100). Are the 100+ courses that don't have any prereqs also hard? When should you take them?</p>

2

<p>Those courses would be upper division courses. As such, expect tougher material and older peers.</p>