1. Rail mass transit is divided into two different systems: Metro Rail and Metrolink commuter trains; the Metro Rail in Los Angeles mass transit mainly connects major attractions such as Downtown, Hollywood, Universal City, Pasadena, and Long Beach.
2. There are quite a few bus systems. The most important one with the widest coverage is the Metro Bus operated by Metro, but it has one drawback: it rarely goes directly to your destination and often requires transfers. Metro Bus is affiliated with Los Angeles County. There are also local bus systems such as LADOT's LA Dash Bus. For detailed information, you can visit their official websites. (In the United States, you can directly send an email to request free mail delivery of tourist attraction brochures or transit route maps to your home. Local tourism introduction websites also often have travel information available for free.)
3. Another one worth mentioning is Dash, which is also a bus. Compared with Metro, its range is mainly around downtown Los Angeles, but its waiting time is longer, and the last bus is at 5:00 PM. However, it is cheaper, and you can also get a free transfer ticket. The best part is that there is a Dash FF station right at USC Gate 5 (on Jefferson Street), so taking it to the old Chinatown for a haircut or something similar is quite convenient.