Yellow Archangel (Lamium galeobdolon) is a widespread garden plant and garden escape. Nice plant to have in the garden- will grow in dry shady spots, has an attractive frosted white marking on the leaves and bright yellow flowers that open clam-like (as is the case with other Lamiums). Bumblebees shoulder open the flowers with great gusto. It's a good groundcover plant (or invasive depending which way you look at it).
 The variegated form commonly found in gardens is an introduction from continental Europe and is generally referred to as subsp. montanum or subsp. argentum and several other synonyms which seem to refer to basically the same plant i.e. with variegated leaves.
 There is however another Yellow Archangel with similar flowers but plain green leaves. If you find yourself in an English wood among Bluebells, Stitchwort and Ramsons you may see it. This form of L. galeobdolon is native to the UK and its presence is an indicator that the wood is ancient.