The hobby of collecting consists of acquiring specific items based on a particular interest of the collector. These collections of things are often highly organized, carefully cataloged, and attractively displayed.

Since collecting depends on the interests of the individual collector, it may deal with almost any subject. The depth and breadth of the collection may also vary. Some collectors choose to focus on a specific subtopic within their area of general interest, for example 19th Century postage stamps, milk bottle labels from Sussex, or Mongolian harnesses and tack. Others prefer to keep a more general collection, accumulating any or all Star Trek merchandise, or postage stamps from all countries of the world.

Some collections are capable of being completed, at least to the extent of owning one sample of each possible item in the collection (e.g., a copy of every book by Agatha Christie). Collectors who specifically try to assemble complete collections in this way are sometimes called "completists". Upon completing a particular collection, they may stop collecting, expand the collection to include related items, or begin an entirely new collection.

The most popular fields in collecting have specialized commercial dealers that trade in the items being collected, as well as related accessories. Many of these dealers started as collectors themselves, then turned their hobby into a profession.

Items and subjects that are popular in collecting include:

• Antiques
• Art
• Autographs
• Automobile license plates (only legal in places where the plates are not government property)
• Book collecting, often by genre (see also bibliophilia)
• Bottles (usually a particular type, such as beer or cola)
• Brand article collecting
  • Coca-Cola
• Butterflies
• Candles
• Coasters
• Coin collecting (also medals and tokens) (Numismatics)
• Comic book collecting
• Crystal
• Currency (Notaphily) - paper currency collecting
• Dolls
• Eggs (Oology)
• Figurines
  • Action figures
• Games
• Keyrings
• Matchbooks
• Memorabilia
• Models
  • Model airplanes
  • Model cars
  • Model ships
  • Model trains
• Patch/badge collecting (Scutelliphily)
• Phone-card collecting
• Postcards
• Recordss (see also Günther Schifter)
• Rocks
• Seashells (Conchology)
• Silver
• Souvenirs
• Stamp collecting (Philately)
• Stickers
• Thimbles
• Trading cards
  • Sports cards
    • Baseball cards
    • Basketball cards
    • Football cards
    • Hockey cards
• Weapons
  • Firearms
  • Knives
  • Swords

One alternative to collecting physical objects is collecting experiences of a particular kind. Examples include collecting through observation (especially popular for transportation, e.g. trainspotting, aircraft spotting, metrophiles, bus spotting), bird-watching, and systematically visiting states, countries, continents, national parks, etc.

Further reading

• Charles M. Schulz, Charlie Brown's Super Book of Things to Do and Collect: Based on the Charles M. Schulz Characters, Random House, 1984, paperback, ISBN 0394831659, hardcover in library binding ISBN 0394931653