---
title: Definitions
slug: api/definitions
description: Learn about the concept of entities and properties in data management with this informative document. Understand how entities store and manage data using unique IDs, descriptive attributes, and designations. Discover the function of lookup properties and 
createdAt: 2022-05-10T10:46:44.000Z
---

# Entity

An entity is the information object through which the data is stored and managed. It describes the structure of the data.
Essentially, an entity consists of:

- a unique ID, which is used in the generic elements.
- Properties: structure and definition of the data attributes.
- Designation.



## Property

A property describes a data attribute of an entity.
Essentially, a property consists of:

- a unique ID
- a name
- data type
- Generic field name (e.g. Custom\_\*\*\*)



## LookupProperty

A lookup property is a property that references a record of another entity. The referencing property has the type "Lookupproperty" and the ID of the referenced entity as data type. In a dataset, lookupproperty type properties are stored with the ID of the referenced lookup dataset. 

**Example**: 
Entity: "Order"
Lookupproperty: Order status
In an order record, the status field does not contain "Finished", but the DataID of the record of the entity Order Status, which stands for the status Finished. 


# N\:M Entity

Technically Identical to Entity. 

Now, spare parts are to be recorded for an order. So that this allocation (reference) can happen, an entity is created, which in the simplest case consists of two properties of the type LookupProperty. One LookupProperty refers to the order, the other one to the spare part. 

Let's assume that there is an entity for orders and an entity for parts. Within the Orders entity, all information about individual orders is captured. Within the Parts entity, information about the possible spare parts is captured. Considered individually, they are two separate entities without reference. 

This creates an N\:M entity in which individual spare parts can be assigned to an order. To use this in the API, the DataId's of the orders and parts must be known to populate this entity. 

![](https://api.archbee.com/api/optimize/9vqSx7YIe-nloIBlmgxLr/6LbUd92nMsQhEkZTMDPsw_nm-rest-api.png)