Flickr is almost certainly the best online photo management and sharing application in the world. Show off your favorite photos and videos to the world, securely and privately show content to your friends and family, or blog the photos and videos you take with a cameraphone.
Imgur is used to share photos with social networks and online communities. You can also view the funniest pictures from all over the Internet. There's no limit to how many you can share or upload, and uploading only takes seconds.