To ask what these tiny critters are?

[lookatthetrees]

Must I burn the house down immediately?

They are tiny, attracted to light.

Only in one room. Door now firmly shut! No windows open.

Help!

Mosquitos or maybe fruit flies? Hard to tell without seeing legs/wings.

Fly spray should do it!

If you have a plant in that room, they possibly came from there.

Does the room have mildew or mould (common in bathrooms)? They might be psocids - tiny harmless bugs. What room is it?