Artist trading cards date back to the 17th century, when creative types exchanged miniature versions of their works so they could study each other's techniques. ATCs also served as advertisements and business cards for the artists, with original art on the front and an informal resume printed on the back. By the late 1800s, Impressionists were trading and selling their art cards in exchange for art supplies or room and board, though ATCs never really caught on until the concept was re-imagined in 1997 by Zurich artist M.Vänçi Stirnemann. Inspired by the idea of sports trading cards, Stirnemann hand-created a collection of 1,200 miniatures and unveiled them in an exclusive exhibit. Visitors couldn't buy the cards but were encouraged to produce their own 2.5-by-3.5-inch cards to trade for cards by Stirnemann. An offshoot of this idea, Art Cards, Editions and Originals (or ACEO's), began when certain artists (possibly influenced by their Impressionist predecessors) began to create cards to sell in addition to trading among themselves. Beginning this Friday evening, the [email protected] presents Put Some Art In Your Pocket! What Is An ATC? This exhibit — which consists of ATCS and ACEOs by Jennifer Burns, Lisa Buchanan, Pamela McVay, Sal Scheibe, Wanda Edwards, Randi Marx, Sonia Reigle, Cassandra VanCuren, Tracie Rozario and Jeffrey Errick — kicks off with a reception from 6 to 9 p.m. Fri., July 13. On display July 13-21, noon-4 p.m. Tues.-Sun., The [email protected], 620 First Ave. S., St. Petersburg, free admission, 727-895-6620, thestudioat620,org.