The pleadings step is the first step or stage of litigation.  It involves several sub-steps: (1) the preparation of a summons and complaint, (2) the filing of the complaint and, technically, the issuance of the summons, (3) the service of the summons and complaint, and (4) the service and filing of an answer.

This summary description of the pleadings step shows that the pleadings step involves three documents: the summons, complaint and answer.  The summons is a form of legal process.  There are only a few forms of legal process.  Essentially, legal process is an order of a court requiring a person to come before the court.  The complaint is the document in which the person bringing the lawsuit, the plaintiff, describes the claims being raised in the lawsuit.  The answer is the document by which the person being sued, the defendant, responds to the claims contained in the complaint.

In addition to responding to the complaint, a defendant may also use an answer to bring  related claims against the plaintiff and other parties.  When this happens, which is not that often, it spawns other documents, such as replies and third-party answers, as well as claims called counterclaims and cross-claims.

This  general description of the pleading stage fairly describes this step in federal court, and it would generally describe most cases brought in New York State courts.  When this general description applies, the technical term for the lawsuit or court case is action.  However, there are several groups of cases in which the documentation used at the pleading stage is different.  In these cases, the plaintiff is called the petitioner.  The petitioner starts the lawsuit with a notice of petition (or order to show cause), and a petition.  The defendant, though now called a respondent, still responds using an answer.  Technically, these cases are not called actions.  Instead, they are called proceedings..