People write diaries for various meaningful reasons that broadly include improving self-awareness, managing stress and anxiety, processing emotions, and preserving memories. Writing diaries helps individuals express feelings freely, gain a better understanding of their thoughts, improve metacognitive skills (how they think about their thinking), and organize their thoughts over time. Additionally, diaries serve as a personal record or time capsule, allowing people to look back on their lives, track changes, and sometimes pass on their experiences to others. Many find diary writing therapeutic and a way to vent or reflect without external judgment, which fosters personal growth and emotional relief.