Time
Transportation schedules and business appointments are often designated using the 24-hour clock. 13.00, for example, is equivalent to 1:00 p.m. For informal social engagements people will tend to use the 12-hour clock designations along with a different terms indicating the time of day. Most commonly used are terms for early morning, late morning, noon, afternoon, evening and late evening. A traditional Thai method of telling time treats 7:00 a.m. as 1 o'clock the morning, 8:00 a.m. as 2 o'clock, etc. This traditional time system is used primarily in the morning hours. A similar system is sometimes used again for the evening hours beginning at 7:00 p.m. For business appointments or formal engagements, people should arrive on time. For informal social occasions, it is polite to arrive anytime after the designated hour; promptness is not expected.