Marinara derives from the Italian word for sailor, marinaro. Due to these origins I have seen many people say that marinara sauce must contain something from the sea, usually anchovies. Actually this is not the case, the origins of marinara sauce are that it is the sauce that they made in Naples for the sailors when they returned from the sea. It is very important to master making a good marinara sauce. Not only is it delicious on it’s own over pasta, but as you will see by browsing this site it is a good starting point for many other recipes.
The quality of your marinara sauce is will be directly proportional to the quality of the tomatoes you use. If you can find San Marzano tomatoes imported from Italy, use those. If not, experiment with the different brands at your local supermarket until you find ones you like.