Answer: you know, diary may serve an intangible role in adjusting one's mood, help to be a good listener to share one's secret, make some long-term or short-term plan.

The reason for keeping personal names secret is that one's name can be used in sorcery.

This is an important part of Hatha Yoga because the yogis of old times believed that the secret to controlling one's mind can be unlocked by controlling one's breath.