A more thorough explanation:

A retainer agreement is a legal document that outlines the terms of a relationship between an attorney and a client. It is a formalization of the agreement between the two parties and sets out the scope of the work to be done, the fees to be charged, and the responsibilities of both the attorney and the client.

For example, if you hire a lawyer to represent you in a legal matter, the lawyer may ask you to sign a retainer agreement. This document will specify the hourly rate the lawyer will charge, the amount of the retainer fee, and the scope of the work to be done. It will also outline the responsibilities of both the lawyer and the client, such as the client's obligation to provide information and the lawyer's obligation to keep the client informed about the progress of the case.

Another example of a retainer agreement is when a company hires a law firm to provide ongoing legal services. The retainer agreement will specify the types of legal services the law firm will provide, the fees to be charged, and the duration of the agreement.

Overall, a retainer agreement is an important document that helps to establish clear expectations and responsibilities between an attorney and a client.