The World Digital LibraryYesterday's Washington Post had an article about the inauguration of the World Digital Library (WDL), on online archive of primary sources being continuously expanded under the sponsorship of UNESCO.1
As explained at the WDL website, the mission of the WDL is to make "available on the Internet, free of charge and in multilingual format, significant primary materials from countries and cultures around the world." The principal objectives of this endeavor include expanding "the volume and variety of cultural content on the Internet," providing "resources for educators, scholars, and general audiences," and building capacity in partner institutions (generally, libraries and archives) "to narrow the digital divide within and between countries."2
The image below is just one example of what you will find at the WDL, which currently has upwards of 1200 items.
(World Digital Library)
When you visit the page on which this image is displayed, you can see the care with which the archivists have assigned categorized tags ("consistent metadata") to assist visitors in finding the image when searching using various filters, such as location, time period, topic, type of item (book, photo, musical score, etc.), and home institution.
1 The WDL website is hosted at the US Library of Congress. The plan is to establish mirror sites elsewhere in the world in due course. (Note that the Library of Congress maintains an analogous program of digitized primary materials relating to the United States the National Digital Library Program which you can read about here.)
2 The languages in which navigation tools and item descriptions are available are Arabic, Chinese, English, French, Portuguese, Russian, and Spanish. The plan is to add more languages over time, but doing so is at a lower level of priority than "increasing the volume and diversity of content from and about all countries in all languages and building digital capacity in developing countries."