The dunnock, a rather undistinguished little brown job, is quite common in the UK, so little remarked upon.
In my youth it was called a hedge sparrow, and this term is still sometimes used.
This one conveniently posed on a post at the excellent RSPB Fairburn Ings, near Leeds. The variegated markings mean it is well worth a second look, and actually quite attractive.
For inexperienced spotters like me, they are easily confused with house sparrows and corn buntings.