Your yard and garden are home to a variety of insects, most of which are good to have around; but, if you can’t recognize the “white hats,” you might mistake them for pests and kill them with friendly fire. Here’s a guide to some common beneficial “bugs.”
“Ladybugs” are beetles. Not all are red or orange with black spots, but they eat aphids and other pests as adult beetles and larvae. Would you recognize a larva lady beetle?
Green lacewings and brown lacewings are delicate insects attracted to your porch light at night. In the larval stage they are voracious predators of aphids, small caterpillars, and other garden pests.
Syrphid flies are also called flower flies or hover flies, and they are mimics of bees and wasps. Many help pollinate flowers; in the larva stage, several kinds eat aphids.
Soldier beetles are fond of nectar and pollen, but also eat aphids and other tiny insects. They are most abundant in spring and fall. They resemble fireflies or blister beetles.
Tiny, stingless wasps are parasites of eggs or larvae or pupae of other insects. Even stinging wasps destroy countless caterpillars, flies, and stink bugs. They sting prey into paralysis and store it in an underground burrow or existing cavity as food for their larval offspring. Most wasps are solitary and gentle, not social and hostile like yellowjackets.
Assassin bugs only “assassinate” other insects, and they are very effective in the war on pests. Note that they are indiscriminate and may also eat the occasional pollinator.
Get a good field guide like the Kaufman Field Guide to Insects of North America to help figure out who is who in the bug game. Full disclosure: I am the principal author.