Notes are a form of written communication or record-keeping, serving to capture key information for future reference, organize thoughts, and aid in memory and understanding. They can be short and informal, such as a reminder to a friend, or detailed records like the minutes of a meeting. The practice of making notes is a versatile skill, applied in various contexts like studying, meetings, and digital communication, using methods such as outlining, mapping, or the Cornell Method to condense and organize information effectively.