A sys_id, or system identifier, is an exclusive alphanumeric code assigned to every record in the ServiceNow platform. Its primary purpose is to uniquely identify individual records. Generated automatically upon record creation, the sys_id remains unchanged throughout the record's existence. It plays a critical role in referencing and identifying specific records within the ServiceNow system. By utilizing the sys_id, efficient data retrieval, manipulation, and operations like record linking, update tracking, and data integrity maintenance are facilitated within the platform.