66b la chu ky dung de chi danh mot quan ly, chu ky nay co the dai dien cho mot doan du lieu, mot ma san pham, hoac mot bien so trong cac hinh thuc thoi gian. Trong tai lieu, so 66b thinh thanh la ky hieu chung co the co nhieu nghia phu thuoc vao ng context. Trong thuc te, nguoi dung thuong su dung 66b nhu mot chu danh cho mot doi tuong nhat dinh.
nguon goc cua 66b thuong tu cac he thong co ma hoa, thiet ke data, hoac dai dien cho de an do hoa thong tin. Dieu nay giup viec sap the va danh ma nhanh hon trong cac he thong kiem soat.
Trong lap trinh va xu ly du lieu, 66b co the duoc dung nhu mot bien chung de tham chi cho cac module. Trong thiet ke database, 66b co the la khoa chinh hoac ma danh cho cac bang lien ket. Tu do, 66b co kha nang tao ra cac huong dan phan tich du lieu, hoi thor va tu dong hoa cong viec.
Dieu dac biet cua 66b la tinh linh dong, de dung chung cho nhieu hien tuong. No cho phep nguoi dung mo phong nghia cua chu ky tu dong thoi, do do tao ra cac ung dung quan trong cho thiet ke phan mem, quan ly du lieu va he thong tu dong. Tuy nhien can luu y diff ma hoa, the he gap hay giai doan de tranh nham vach.