A line of toys put out by Fisher Price. They live up to their name quite well, being small plastic people slightly larger than Lego wo/men and have little holes in their bottoms (take that however you want to) serving absolutely no purpose other than to have children stick their forefingers into them and getting their fingers wedged inside so that you have to rush them to the hospital to have the damned thing removed.
Their origins go back to the first Little People set released in 1959 with some not-so-small people, a Safety School Bus.
Most people remember the barn set the most, released in 1968 and produced for two and half decades more before Fisher Price stopped making these toys.
Almost everybody had at least one of these sets when they were a kid, but very few actually remember it.