# Items versus copies

This is the most important page in the documentation. The difference between an item and a copy is the one idea that makes KolleK different from a plain list, and nearly every other page assumes you know it. It takes two minutes to learn.

## The distinction

An **item** is the *kind of thing*. A **copy** is *one physical instance you actually own*.

"Amazing Spider-Man #1" is an item. The slightly worn one in Emma's long box is a copy. The near mint one she bought at auction is another copy. Same item, two copies.

- Own three of the same comic? That is **one item with three copies**.
- Each copy has its own [condition](https://getkollek.com/en/docs/core-concepts/conditions), its own storage [location](https://getkollek.com/en/docs/core-concepts/locations), its own value, and its own [history](https://getkollek.com/en/docs/core-concepts/copy-history).
- The item holds everything the copies have in common: the name, the description, the photos, the custom field values, the tags.

## The rule to remember

Descriptive and classification details live on the **item**. Everything about condition, location, money, and history lives on the **copy**.

Ask yourself: "would this be true of any copy of this thing?" The writer of the comic is the same for every copy, so it belongs on the item. What you paid is different for each one, so it belongs on the copy.

## A worked example

Priya catalogues a 1968 Omega Speedmaster:

- The **item** carries the name, a description, photos, and custom fields such as Brand, Model, and Movement.
- Her first **copy** is graded Used, lives in her display case, and carries the price she paid in 2019 plus a professional valuation.
- Her second **copy**, inherited from her grandfather, is graded Worn, lives in a safe, and carries an insurance record and a provenance trail going back to 1970.

One watch as a concept, two very different physical watches, each fully tracked.

## What a copy records

Beyond condition and location, a copy carries an optional identifier (a serial or slab number), a status, a quantity, a note, and an estimated value. The status covers the whole life of a copy: Owned, Ordered, Loaned out, Sold, Gifted, Lost, Stolen, Disposed, or Other. The details are in [Track the copies you own](https://getkollek.com/en/docs/core-features/track-the-copies-you-own).

What you paid and what a copy is worth are not typed onto the copy directly. They come from its transactions and valuations, part of [a copy's history](https://getkollek.com/en/docs/core-concepts/copy-history).

## The mistake to avoid

:::note
Two of the same thing are two copies of one item, never two items. If you are about to create "Amazing Spider-Man #1 (second one)", stop and add a copy to the existing item instead.
:::

Duplicated items split your history and your statistics. One item with many copies keeps the catalogue tidy and lets each physical piece tell its own story.

## Where to next

- Record your copies in [Track the copies you own](https://getkollek.com/en/docs/core-features/track-the-copies-you-own).
- See what a copy can remember in [A copy's history](https://getkollek.com/en/docs/core-concepts/copy-history).
- Capture money correctly in [Record what you paid and what it is worth](https://getkollek.com/en/docs/copy-history/record-payments-and-value).