I can remember when I thought every small brown ground-feeding bird was just a sparrow. Perhaps it's no wonder, as I'd hardly notice a sparrow before seeing him/her flee in the opposite direction. But when I started to set aside time to quietly observe birds in their environment, it became clear that sparrows are anything but one-in-the-same. After I figured out the identity of the abundant and bold supermarket sparrows, I shifted my attention to this shy bird hanging out in the shrubs in my backyard.
Meet Song Sparrow. This species sings loudly and proudly in a variety of habitats and is found throughout most of the United States and Canada. Keys to identification include: brown stripes on gray head, brown patches extending from lower corners of stout gray bills, sides of bird with brown streaks, and chest with an often conspicuous -- you guessed it -- brown spot.
Lacking binoculars to verify these details, one can also learn their song, which can vary from bird to bird but usually starts with two or three introductory notes followed by a jumble of phrases and/or trills. Here's an example from one Song Sparrow who lives near me: