Stamp collecting: The enjoyable, old hobby that is coming back

They are tiny pieces of art, the stamps that we have used our whole lives.

Maybe they are easily forgotten by some, but not to the lovers of Philately; stamp collecting.

Stamps have a robust history, reflecting nearly every interest, holiday, country, and era.

Arguably the first classic stamp was printed in 1840 in England. Known as the Penny Black, it was the first stamp to have adhesive with a face value of one penny. It featured the profile of Princess Victoria. More than 68 million were printed and, today, it is one of the world's oldest stamps with about 1.3 million in existence. Unused Penny Blacks can sell for thousands of dollars.

By 1850, 20 countries were printing stamps, and they contributed to the knowledge of geography.

Like coins, the most expensive stamps in the world are misprints. The 1918 red and blue U.S. airmail stamp featured a biplane, but some of the planes were mistakenly printed upside down. Today if you have one of those, the estimated value is $1.5 million.

King Henry VII was a stamp collector and so was Franklin D. Roosevelt.

Although stamp collecting has been used as a sort of investment, most stamp collectors do so out of simple interest. People specialize in stamps: Stamps from certain countries or certain holidays like Christmas stamps. Some might collect just stamps from certain eras. Others might collect just pictures of their favorite stars on stamps, or musicians like the Beatles.

Two of the most popular stamps in history featured popular people. The 1981 marriage of Diana to Prince Charles sparked a huge interest in the stamps commemorating their marriage. They were everywhere. Even North Korea printed stamps of the wedding.

In 1993, the iconic Elvis stamp was the last really popular stamp that caught the imagination of the public.

Most stamps are not expensive, but even recent stamps will be sold slightly over the face value.