Realmente no he visitado Los Ángeles. Sólo conozco la estación de autobuses (Greyhound), donde he parado para hacer varios trasbordos. Dicho esto, la principal impresión que me llevo de la ciudad es que es un atasco infinito.
I haven't visited LA, only know Greyhound bus station, where I stopped to change buses three times. That said, the main idea I've got of the city is an everlasting traffic jam.
GREYHOUND
Viajar en transporte público en Norte América no es tan usual como en otras partes del mundo. Si no tienes coche, muchas veces es difícil desplazarte. Además, cuando comentas por aquí que estás viajando en autobús, mucha gente se sorprende. Me han comentado varias razones por las que no tiene buena fama, sobre todo relacionadas quién se supone que lo utiliza : gente con problemas psicológicos (a los que meten en el primer bus que salga para que se vayan de la ciudad), gente recién salida de la cárcel, o sencillamente aquéllos que no pueden comprarse un coche. No sé si será cierto (o si son razones para evitar coger autobuses), pero en mi caso, no he tenido el más mínimo problema con ningún pasajero en más de 6 meses.
Travel by public transportation in North America is not so usual like other parts of world. If you don't have a car, travel sometimes is difficult. When I say I am travelling by bus, lot of people are surprised. I've been told some reasons why travelling this way has bad name, specially because of the people are supposed that take these buses: people with mental disorders (who are seated in the first bus that leave the city), prison inmates just released, or people who can't afford a car. I don't know if it's true (or if they are reasons to avoid taking buses), but I haven't had one problem with other passengers in more than 6 months.
I've used mostly Greyhound.It's the company that services more destinations.
Buses and stations have Wi-Fi. It usually works.
Greyhound in San Francisco. Except few cities, each company has its own station.

The sistem to board the bus: there are several lines, but I don't know exactly the reasons ( if you are re-boarding the bus or you are going to transfer, etc). I was adviced to arrive early and line, just in case the bus is full. I should wait for the next bus.