A more thorough explanation:

A deposition is a witness's testimony that is recorded in writing for later use in court or for discovery purposes. It can be taken in response to oral questioning by a lawyer or in response to a prepared set of written questions.

• Deposition on written questions: A deposition given in response to a prepared set of written questions, as opposed to a typical oral deposition. For example, a lawyer may send a set of written questions to a witness, who then responds in writing. The officer records the answers, transcribes and files the deposition as with an oral deposition.
• 30(b)(6) deposition: Under the Federal Rules of Civil Procedure, the deposition of an organization, through the organization's designated representative. For example, a party may take the deposition of a corporation. The notice of deposition may name the organization and may specify the matters to be covered in the deposition. The organization must then designate a person to testify about those matters on its behalf.
• Apex deposition: The deposition of a person whose position is at the highest level of a company's hierarchy. For example, a CEO of a company may be deposed. Courts often preclude an apex deposition unless the person to be deposed has particular knowledge regarding the claim, and the requesting party cannot obtain the requested information through less intrusive means.

These examples illustrate how a deposition can be taken in different ways and for different purposes. A deposition on written questions allows lawyers to ask questions without being present, while a 30(b)(6) deposition allows an organization to designate a representative to testify on its behalf. An apex deposition is reserved for individuals at the highest level of a company's hierarchy and is only allowed under certain circumstances.