How do you make those salsas that come with the tacos at almost every taco restaurant?

i live in san antonio and often stop by bill millers to buy a carne asada taco, and most of the time they offer me two different kinds of salsa that they put in little plastic containers. one of the salsas is reddish brown, and the other is green. i just want to know how to make it so i can serve it with home made tacos. thank you in advance.