HistoryPin is a Google Maps mashup that allows visitors to pin historic photos on a map and to view photos across locations and dates. The site offers a video introduction and tours of some of the best content. For more details on using the site, read The Internet Patrol.

Identifying a mystery celebrity in a photo, or finding websites that have stolen your copyrighted images has gotten a whole lot easier with Google’s Search by Image. Images can be dragged and dropped, uploaded, specified by URL, or (with a Chrome or Firefox extension) simply right-clicked. To see Dave Taylor ID a mysterious blonde, read Can I Identify a Photo Using Image Search?.

Facebook introduced a new profile page layout as a user option a few weeks ago. This new layout includes a horizontal grid of five photo thumbnails, flanked, on the left, by a profile picture. Inspired by French artist Alexandre Oudin, more and more Facebook users are experimenting with clever juxtapositions of these thumbnails. Check out Mashable for a gallery of ten creative profile pic hacks.

WebP (pronounced “weppy”) is a new open-source image format, designed by Google, that uses a compression algorithm that produces smaller files than currently popular formats such as JPG and PNG. And smaller image files mean faster loading web pages. Hooray! In order for WebP to take off, however, browsers and graphics software would have to adopt it. Google is doing their part for faster loading web pages by including WebP in an upcoming Chrome release. Learn more at Google or Ask Dave Taylor.

Today’s Photoshop tip from Melissa Clifton is for fans of pop artist Andy Warhol. Her Andy-Warhol-Up Your Photographs is a tutorial for beginner to intermediate Photoshop users who want to turn a plain photograph into a colorful piece of art.

This month marks the twentieth anniversary of the Adobe Photoshop. In the last twenty years, “shopped” has come to mean manipulated with an image editor, and “photoshop” is sometimes used as a verb. Here on Adobe TV, is a television snippet that explores Photoshop’s early years.

Google Image Search is perhaps the best know image search engine. But MakeUseOf reveals five others worth knowing about, including Cyclo.ps, a meta-search engine that lets you search up to eight stock photo sites at once, including Flickr, Shutterstock, and Photos.com.

Have you ever seen a collage made of hundreds of little photos and wondered how it was done? One way is with Shape Collage, a free, easy utility for both Windows and Mac. Simply download Shape Collage, pick a shape, point it to your photo folder, and watch it work its magic.

As with any computer media, it is possible for your camera memory card to get infected with a computer virus if you connect your camera or your memory card to an infected computer at a friend or relative’s house. When you return home, it is then possible to infect your own computer by attaching the camera or the card to your system. Learn more about how to keep your systems safe from Ask Leo.

Picassa photo management lets you geotag your photos using a map view. To tag multiple photos in the same album, click Map Photos, and then drag your thumbnails onto the map. For instructions on how to tag single photos, and entire albums at once, read Google’s Picassa Help.