Entity
An entity can be thought of as a category or type. Each occurence of the entity is referred to as a document.
For example, let's say you create a CD collection using Angular. The entity is CD. Each CD in your collection is labeled as CD to identify it as belonging to the same type. Each entity, in this example, each individual CD, is referred to as a document of type CD. The document stores unique information about a particular CD, such as release date, artist, individuals tracks, etc. You determine the information you want to store.
As a convention, entity names start with a capitalized letter while document names start with a lower case letter.
Entities are declared in your template using the ng-entity attribute.