The three types of ageing are biological ageing, psychological ageing, and chronological ageing. Biological ageing encompasses natural changes in the body over time, affecting organs, senses, and overall physical health. Psychological ageing relates to changes in behaviour, cognition, and emotional responses influenced by brain function and life experiences. Chronological ageing refers to the passage of time and the numerical age of an individual, serving as a marker for tracking and understanding various life stages and milestones.