2. Calendar is a daily newspaper used to record time. The first calendar in China was about 4000 years ago. According to a page of Oracle bone calendar in Oracle Bone Inscriptions, it is proved that the calendar of Yin Dynasty has reached a considerable level. This page of Oracle Bone Inscriptions is the oldest almanac of all mankind, and this page of Oracle Bone Inscriptions is also called the calendar. But the real calendar appeared. About 1 100 years ago, during the Yongzhenyuan period in Tang Shunzong, the imperial calendar was already used in the palace. Each page displays a calendar for one day, a monthly calendar for one month and an annual calendar for the whole year. Other time elements included in the calendar are solar terms, century and year. Calendars come in many forms, such as wall calendars, desk calendars and calendar cards. And then the electronic calendar was developed.