# Main Concepts

This section defines the main concepts of MeiliSearch.

Important

MeiliSearch is an asynchronous API. This means that, unlike a synchronous API, it doesn't wait for the call to be done as calls are placed in a queue for processing. For further information please read the advanced guide.

# Glossary

The following key terms are used in this documentation. Before going any further, it is recommended to become familiar with them.

  • Index: An index is the entity that gathers all the documents of a given structure. It can be comparable to a table in SQL.
  • Document: A document is an object which contains defined attributes and their associated data.