Ladybug, Ladybug, Fly Away Home
I grew up calling them ladybugs. I've also heard them called lady beetles and ladybirds. When I was a kid, they were wonderful. Brightly colored, no stinger, didn't bite. One of the "good guy" bugs.
In Georgia we got a lot of them crawling around inside our windows sometimes. That was nothing compared to this old farm house.
The ladybugs that swarm and invade are Asian Lady Beetles. They overwinter in attics, siding, and behind baseboards. I vacuum mine up. They make the vacuum bag stinky inside. About the third time I vacuum up ladybugs, the vacuum cleaner is whooshing foul odors throughout my house.
They congregate mostly in my windows, but I sometimes see them other places. If you are infested with lady beetles, or think you are, you should read this excellent article put out by the University of Kentucky. It won't really help you get rid of them, but maybe your ladybugs won't bother you so much after you read the article.
Ladybugs don't carry disease, they don't eat wood or wiring or otherwise destroy your home, and they don't breed indoors. They're just hanging out waiting on warm weather and plotting their big escape. They eat unbelievable amounts of aphids. My garden is gonna love 'em.