Wikipedia:Wikipedia is not a file storage service
 | This is an essay. It contains the advice or opinions of one or more Wikipedia contributors. This page is not an encyclopedia article, nor is it one of Wikipedia's policies or guidelines, as it has not been thoroughly vetted by the community. Some essays represent widespread norms; others only represent minority viewpoints. |
 | This page in a nutshell: Wikipedia is not a free file hosting service. Files should add value to the article space, or they should be deleted. |
Note: In this essay the technical term "file" is used. While "file" also includes sound clips, video clips, and portable documents (ex. PDFs), in the context of this essay "file" can be understood to mean "image".
Wikipedia is an encyclopedia. Pursuant to the aim of creating a comprehensive and useful resource, Wikipedia allows for, and encourages the use of, files. Many tens of thousands of articles use files to great affect, including the majority of the articles considered to be Wikipedia's best.
However just because a user has the technical ability to upload a file does not necessarily mean that they should upload it. There are many things to consider before uploading a file, including copyright, privacy, and even how your reputation might change from uploading the file.
As important as copyright, privacy, and reputation are, it is also important that every file on Wikipedia be usable and used in the article space. Wikipedia is not a repository for files, it stores files that are used on Wikipedia, and should only store files used on Wikipedia. Budding photographers who want to show off their work can upload files to Wikipedia if those files can be used constructively in articles, however forcing a file into an article when it isn't a good fit is discouraged. If you honestly believe that the file can help, say in an article with no files or in an article where your file is better than the existing files, then feel free to upload, however if you just want to show off your work, there are better venues.
Flickr is a well known file hosting site. You can set up an account there and upload whatever you want (assuming that you follow Flickr's rules on content). Files that are altered, say by removing objects, adding artistic filters, or messing with the coloring, are not generally welcome on Wikipedia, where accuracy is a major concern, however there are no such restrictions on Flickr. Uploading self-portraits to Wikipedia, with rare exception, is frowned upon. Uploading them to Flickr is accepted. Wikipedia and Flickr have fundamentally different purposes and objectives; The two should not be confused with one another.
There are exceptions to the expectation that files be used in the article space. A number of files are used primarily or exclusively in the user space or project space. Those files, however, have a clearly defined purpose and are utilized constructively on a consistent basis. Things such as Barnstars, Wikiproject icons, and template icons all are valid exceptions. Most of these files, however, are hosted on Commons. There are also a limited number of self-portraits on Wikipedia that are, if not endorsed, not berated. Editors with hundreds of edits and a well established presence occasionally add files to their user pages. There is no set number of edits or fixed length of time where uploading a self-portrait becomes tolerated, however a dozen or two dozen edits isn't past that line, and editors whose only contribution is the uploading of a self-portrait should not be surprised if the file is deleted.
There are other options for people that want to contribute but don't know where to place a file. Wikipedia has a sister project, Commons, which stores free use files. While files on Commons still have to be free of deliberate distortions, and are expected to be reusable by others, at least theoretically, Commons does not require that a file be used for it to be stored there. files on Commons can be used on Wikipedia directly, there is no need to upload it on Commons and on Wikipedia, so some people argue that all free use files be uploaded to Commons. As indicated, Commons is not Flickr either, and should not be treated as such, however their leniency on use and immediate value make it a good place to upload files, especially if you're not 100% sure that they meet Wikipedia's stricter standards, but still want to try and use them in an article.