Syrphid flies like the one above (Eristalis arbustorum, Syrphidae) are also known as flower flies or hover flies. Many bear a superficial resemblance to bees (Apidae), but the one shown here looks more like a horse fly (Tabanidae) to me.
Despite their Batesian mimicry of venomous and biting insects, syrphid flies are generally harmless or even beneficial to humans . Adults feed on nectar and many serve as important pollinators. Some larvae feed on aphids and thrips, which are highly damaging pests of agricultural plants.