Postcards come in many different styles, depending on the copyright era and the manufacturer of the postcard. The styles range from the late 1800s and early 1900s when postcards were addressed on the backs only and your message was written on the front, usually on the bottom edge or the right or left hand side in a small space. The backs on these types of cards were solid backs with no dividers and were for the address only.
The next type was the split back postcards that came out in the 1910s. These postcards has a line running vertically down the middle of the backs with one side for the address and one side for the message.
The type of cards to come out in the 1930s through the 1950s were the linen style postcards which had a textured front to them, which could be seen and felt and were very different from the plain color type postcards. In the 1950s to the present is the era of the chrome postcard. Which is typically the style of postcard which you find today.
Postcards were also manufactured as real photo cards which were produced using real photos taken of the view. During World War II, comic or joke type postcards were very popular.
Some postcard makers included: Curteich Postcard Company, The Albertype Co, Tichnor Quality Views, Dexter West Nyack NY, Dexter Press, Valentine Black Co LTD, Colourpicture Publishers Inc, E C Kropp Co, The L L Cook Co, Aurora Postcard Company, Metrocraft, Canadian Postcard Company, The Tecraft Company, Hiawatha Card of Detroit, Tom Neel Color Cards, Marken & Bielfeld Inc, Koppel Color Cards, NYCE Manufacturing Co Inc, Mayer Postcard Company, Ward Beckett & Co, Max Schwartz Company, Newman Postcard Company, Young Lord & Rhoades, and many local companies.
Many but not all of the postcards have catalog numbers, the Curt Teich numbers will tell you what the publishing date is for the card.
Many cards will also have nice writeups on the back, some have none, along with publishers info, some will have a copyright date on them also.
Postcard collecting is interesting because there are so many different types of collectors, because there are many different types of cards available. Postcards from the 1800s are desireable, and people collect from different eras. The 1930s to the early 1950s was the era of the linen postcard. Into the later 1950s to present time the chrome postcard was the prominant card made, its the card you see
in stores now. Some people like used cards with a postmark and stamp still on them, others like the unused cards because the postcards were damaged by postmarks, and bent and damaged in other ways during delivery.
Some people like the real photo cards, and other like the fancies, or joke cards too. Many collectors will only collect cards of a certain City or State or region. Other collectors like certain objects or themes, some collectors like Lighthouse postcards, or Amusement Park Cards. Another popular type of cards were the one featuring transportation, there are postcards of Airplanes, Cars, Trains, Ships, Military cards and more.
Another popular type of postcard were the ones featuring Lakes, Waterways, Fishing Resorts, Vacation areas, and Hotels and Motels. One very popular city is Las Vegas, many people collect Postcards of Las Vegas.