first aid is promptly helping people who are suddenly sick (illnesses) or hurt (injuries or body damage). For example, first aid is used at accidents to help an injured person until they receive medical treatment (help by doctors, nurses or ambulances). First aid is also used to help people who suddenly become sick, until help arrives or they can be taken to medical care.  

A person does not need much equipment to give first aid. A package of things useful to give first aid is called a first aid kit. Lives can be saved even without a first aid kit. What is required is basic knowledge. First aid can be done just about anywhere that an emergency requires. In places far from hospitals, first aid may be the only help possible until the person can be taken to a hospital or clinic.  

Emergency medical dispatchers are trained in first aid, so that if there is an emergency, they can give the caller some information on what to do until the ambulance arrives.