Common name purslane. It's an annual weed, related to moss rose. It is a common weed, but edible, and in fact I think one of the best edible weeds. Many weeds are "edible" in the sense that they are not harmful and may have lots of nutritional and medicinal values, but wouldn't give you much pleasure to eat. Purslane is tasty. I have a purslane potato salad recipe I really like. It is in fact very high in vitamin E and an omega-3 essential oil. It also has Vitamin A, Vitamin C and some anti-oxidants.