What do e16 and e19 mean in the US green card?

The meaning is as follows:

E16 and E19 indicate the type of green card, that is, the channel through which the green card holder obtained the green card. E16 indicates the green card obtained through the EB1A skilled immigration method, and E19 indicates the type of green card held by the spouse of the main applicant for the E16 green card.

The term green card originated in the United States, because the earliest permanent residence permit in the United States was a green card. With the change of design, 20 versions have been updated, but the name green card has been retained. . In May 2010, the green card became green again, changing from the previous white background with yellow-green patterns.

U.S. Green Card

The official name of the U.S. Green Card is "Permanent Resident Card (Permanent Residence Card)", also called I-551, which records the cardholder's photo, fingerprint, Name and other information can be obtained through application. Applicants usually need to have a permanent job in the United States or have a spouse and children who have settled in the United States. If the application is successful, a green card will be issued to the applicant, and the cardholder needs to renew the card on schedule.

Reference for the above content: Baidu Encyclopedia - Green Card