This is generally described as the official court-allowed taking and recording of the oral testimony of a witness outside of the court.  Depositions are usually performed by the law firm hired to work, the case, but in some cases it can be outsourced to third party legal service providers, at the request of a trial attorney.  Usually the person is recorded on video and audio.  They are then asked questions by both sides of the case.  This recorded evidence is to be presented later in the trial if it is deemed as admissible evidence.

Lawyers take great care during a deposition to ensure that the witness is clear about the question being asked, and that they respond in an appropriate manner.  For example: “uh huh”, is not an accepted response to a question.  “Yes” must be stated instead, to ensure there are no misunderstandings in the answers given by the witness.

Example

During a divorce trial,  a Guam divorce lawyer calls for a deposition in his conference room as part of the discovery process.  The purpose of this is to gather evidence to be presented to the trial judge to be used as admissible evidence in the upcoming contested divorce trial.