Online photo sharing sites have numerous advantages over keeping pictures on your hard drive at home – they make it easy to share pictures with others, provide a central repository of images for use in your blogs or tweets, give you web 2.0 features like tags to organize your photos and enable searching, and offer worldwide exposure for your work. Access control lets you decide who can see which photos, and links to other services make it easy to edit your images, embed them in your blog, or order products from them like reprints or mugs. Among potential downsides are privacy and copyright concerns, although the concept of Creative Commons is one way to enable “fair” use. There is now some overlap with other services as photo sites also let you share videos.

Flickr is one of the earliest and most popular photo sharing websites. It was started in 2004, and was later purchased by Yahoo! When you create a flickr account you will use Yahoo! credentials, which can also be used to log in to other Yahoo! services.

By the end of 23 Things, I hope to use some of your flickr photos of Oxford libraries to create our own iGoogle theme. The theme will be dynamic, changing throughout the day, so photos taken at different times of the day/night would be ideal.