Researchers say a dozen of them are bad enough to cause explosions.
The fluffy-white hunters are everywhere this year, from New York to Baltimore all the way down to Florida.
A new map showing the carbon footprint for nearly every zip code indicates that suburbs are powerful greenhouse-gas emitters.
This outdated tradition may cause new mayors more headaches than its worth.
More proof that 'on-time' performance metrics don't actually tell us very much.
New York in 1776, Charleston in 1780, Baltimore in 1801.
At last, historians have charted the great "squirrel experiments" of the 1800s, which saved the humble creature from urban extinction.
Parts of California and New York are much richer than Washington, but they often belong to larger counties that include areas with poorer residents.
Familiarity and social ties influence our decision to intervene on behalf of others.
Alongside every other building in Washington, D.C.
Median incomes have been growing the fastest, however, in a very different part of the country.
Memorials and tributes to the South African icon, from Soweto to Brooklyn.
He'll be calling in to Washington, D.C.'s crude "The Sports Junkies" show.
A group of Washingtonians say micro-dwellings are the future. But problems abound.
This wonderfully poisonous map shows what Yahoo!'s search engine thinks of places, such as "Chicago is so two years ago" and "Philadelphia is ugly."
And other eye-popping comparisons.
It's one of the few cities to emerge from the recession unscathed. But for its economy to keep growing, Washington must wean itself from the government.
The shift from close-in spaces to far-flung outposts like Denver International reflects changes not only in travel, but in the culture.
Ninety-two percent of new diagnoses occur in just a quarter of U.S. counties, and most of them are urban.