Grand-taxi means "big taxi" in French. Every city in Morocco has a system of petite (small) and grand-taxis. It took me a while to figure it all out, but once I did, getting around was very easy!
Morocco has great public transportation. In the bigger cities, like Rabat and Casablanca, there are tramways. Every city has buses and there are many bus (and train) lines that go all over the country. Tetouan, as you know, is a smaller city in the north. It was the first city in Morocco to have a train station but it was destroyed in the fight for independence in 1956. Now, it just has buses, grand-taxis, and petite-taxis.
I felt lost. Petite taxis will take you anywhere within the city limits and grand-taxis will take you from city to city along routes. I didn't know the routes of the grand-taxis or anything about the city's geography. I learned that grand-taxis are different colors based on what cities they are going to and coming from. I also learned that when you are in a petite-taxi, you are supposed to tell the driver the neighborhood you want to go to, and give directions when you get there. Most taxi drivers don't use street names because they don't know them, or they can't read.