I am a newbie to cooking. Is this what is called a marinara sauce?

I think the recipe is a marinara sauce--which is basically tomatoes, garlic, and herbs. Check some of the old reliable Italian cooking sources to compare the marinara recipes. With Italian cooking (and just about every other ethnic cuisine), there are regional variations. Everyone thinks the recipe from his region (and his Mama!) is the best. Good tomatoes make good sauce. Use the right variety of tomato--one grown for sauces. If fresh tomatoes are out of season, then look for San Marzano tomatoes grown in southern Italy. That will pretty much assure a good sauce.

If you're looking for a good sauce for pasta, I can recommend this one: http://food52.com/recipes/13722-marcella-hazan-s-tomato-sauce-with-onion-and-butter

Just had a look at that recipe. As simple as Marinara is, that is not one. Real Marinara is simply tomatoes (usually canned, but certainly at this time of year, fresh!)and garlic, slowly cooked together into "submission." Lots of folks call lots of different tomato sauces "Marinara," but my Italian friends who cook/teach cooking for a living all aver that it's just tomatoes and garlic.