Plant I found (the creeping woodsorrel)

I know that I've seen this a lot, and I should know what it is, but I have no idea. Brandon B.
Taxonomy:

Kingdom	Plantae – Plants
Subkingdom	Tracheobionta – Vascular plants
Superdivision	Spermatophyta – Seed plants
Division	Magnoliophyta – Flowering plants
Class	Magnoliopsida – Dicotyledons
Subclass	Rosidae
Order	Geraniales
Family	Oxalidaceae – Wood-Sorrel family
Genus	Oxalis L. – woodsorrel
Species	Oxalis corniculata L. – creeping woodsorrel		posted by Brandon S.