This is a vintage 1c stamp issued in 1936. The first in a series honoring army heroes, this stamp features revolutionary war Generals George Washington, who went on to become the first US President, and Nathaniel Greene.
The stamp is accompanied by a hummingbird stamp, a stylized design by Nancy Stahl in shades of green and blue.
1c used to be enough to send a postcard.
Currently the cost is 35c to send a postcard domestically, however on April 10 it will be reduced to 34c when the exigent rate increase expires, much to the unhappiness of USPS.
First class letters will decrease by 2c to 47c, and the extra ounce price will reduce to 21c. A 2 oz letter will therefore cost 3c less (68c), and a 3 oz letter will cost 4c less (89c).
International letters will decrease by 5c to $1.15.