Interrogatory is a written question directed by one party to another regarding information that is within the scope of discovery. When you are issued Pattern and Non-Pattern Interrogatories, you will notice that they are simply a series of questions that require an answer.
Interrogatories are part of the discovery process of divorce. They allow you and your soon-to-be/already ex spouse to ask questions that must be responded to in writing under oath. These answer are then used to determine facts in the case, as well as to question each side if/when the case goes to trial.
Legal separation is a legal process by which a married couple may formalize a separation while remaining legally married. A legal separation is granted in the form of a court order. In cases where children are involved, a court order of legal separation often makes child custody arrangements, specifying sole custody or shared parenting, as well as child support.