This entity is a root-level object. It represents a contact. It is serialized in JSON and saved in the underlying icure-contact CouchDB database. The contact is the entity that records the medical information about the patient chronologically. A visit to the patient's house, a consultation at the practice, a phone call between the patient and the healthcare party or integrating lab reports into the medical file are examples of when a contact can be recorded. A contact can occur with or without direct interaction between the patient and the healthcare party. For example, when a healthcare party encodes data received from laboratory's test result, this is done in the absence of a patient. A contact groups together pieces of information collected during one single event, for one single patient and for one or more healthcare parties. Patient's complaints, the diagnosis of a new problem, a surgical procedure, etc. are collected inside a contact. The main sub-element of the contact is the service. Each atomic piece of information collected during a contact is a service and is stored inside the services list of a contact.