Red card: a red card refers to a person who has been diagnosed or suspected to be in close contact with a patient and needs to go to the hospital for quarantine as soon as possible.
Orange card: An orange card means that you have been to the middle-high risk area within 14 days and need to be quarantined for 14 days.
Huang Ka: Huang Ka arrived overseas on 14.
Green card: A green card represents health and has nothing to do with patients.
Trip code principle: Using the signaling data of the mobile phone, the user's location information is obtained through the location of the base station where the user's mobile phone is located. Communication Big Data Travel Code is a free inquiry service provided by China ICT Institute in conjunction with China Telecom, China Mobile and China Unicom through the location of the base station where the user's mobile phone is located by using the signaling data of the mobile phone, so that mobile phone users can inquire about all the city information they have visited in the previous 14 days through this service.