How to share photos online for free

Only professional web sites and mature that are online and have many users.

Allow for open content

 * flickr - free membership (3 photosets, 20MB/month). See also flickr graph
 * ourmedia - in collaboration with the internet archive, video also
 * openphoto
 * buzznet
 * care2 - use the Gallery2 free software.
 * pictiger - Quick hassle free uploader with no registration. Provides links with thumbnails for use in forums.

Category unknown

 * fotothing - free membership (5 pictures/day of < 2MB)
 * photoblog -
 * coppermine not yet an online service but the software used to run such a service (must be moved elsewhere in the future, not deleted!)
 * fotki

Related howtos

 * Forum hosting sites (What are the best free online)
 * Video sharing sites (What are the best free online)
 * Photo publishing (What are the main free software for)

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