1777:  The Continental Congress approved the design of a national flag. Since 1916, Americans have commemorated the adoption of the Stars and Stripes. Prior to 1916, many localities and a few states had been celebrating the day for years. Congressional legislation designating that date as the national Flag Day was signed into law by President Harry Truman in 1949. To date, there have been 27 official versions of the flag, but the arrangement of the stars varied according to the flag-makers' preferences until 1912 when President Taft standardized the then-new flag's 48 stars into six rows of eight. The current version of the flag dates to July 4, 1960, after Hawaii became the fiftieth state on August 21, 1959. (Source: Library of Congress)