An appreciation letter is a formal document used to express gratitude and recognition for someone's efforts, achievements, or contributions. It typically highlights specific actions or accomplishments that are valued, conveys sincere thanks, and acknowledges the impact of their work. The letter often includes personal or organizational sentiments and may offer encouragement or further opportunities. Its tone is positive, respectful, and motivational, aiming to reinforce the recipient’s value and inspire continued excellence. This letter strengthens relationships and boosts morale.