Flickr is almost certainly the best online photo management and sharing application in the world. Show off your favorite photos and videos to the worl...

Twitter is without a doubt the best way to share and discover what is happening right now.

Jeff Koehler is a writer, photographer, cook, and traveler. His titles include La Paella and Rice Pasta Couscous, both published by Chronicle Books

foursquare

Facebook is a social utility that connects people with friends and others who work, study and live around them. People use Facebook to keep up with fr...