A one-year license entitles you to the use of the software for one year. If your subscription is still active, the validity of your licenses will be renewed for a further year. The yearly subscription includes all minor updates (e.g. 2.1, 2.5 etc.) and all major upgrades (e.g. from 2.5 to 3.0). If you cancel your subscription, your licenses will expire one year after the last successful payment.
A perpetual license entitles you to an unlimited use of the licensed major version (e.g. 2.x). Minor updates (e.g. 2.1, 2.5 etc.) are always free. Major upgrades (e.g. from 2.5 to 3.0) are free for 2 years beginning with the date of purchase.