The document defines a selfie as a photograph one takes of oneself using a digital camera or smartphone, especially for posting on social media. It notes that selfies can be beneficial as reflections of self-exploration and a way to express moods and share experiences, especially for those who find communication difficult. However, the document also states that taking too many selfies can lead to loss of self-confidence and "Selfie Disorder." It advises setting limits and ensuring safety when taking selfies.