collection means lots of something, abundance. It is a word from the Latin term acervus (collection).
In general, the word is used to refer to a collection of works or goods that are part of a heritage, whether privately or publicly owned. This heritage can be artistic, bibliographical, scientific, documental, genetic, iconographic, historical, etc.
A collection can belong to a particular individual, an institution or a nation.
The cultural heritage of a people is the cultural and artistic manifestations, made up of traditions, customs and habits that are passed between generations. In general, the cultural and historical collection is organized in a museum, an institution par excellence that investigates, collects, preserves and exhibits works.
The bibliographic collection consists of books and other documents stored in a library. A document collection groups all documents referring to a specific issue. For example, the public archive of a city makes available all the historical documents referring to the city in question.
Digital collection is a set of works available on the Internet for consultation.
In a legal context, collections are all the assets that constitute an inheritance, the patrimony.