Most people are still used to the old model of buying and downloading software. New versions will come out, and then they would upgrade if they need them. That model is going strong, but for most larger more expensive applications, the subscription based model is taking over. Adobe, creators of Photoshop, Lightroom etc, have switched to this subscription based model. So how does it work?
There is no longer a single one off purchase model available in most territories. You select what you want, either the whole suite or any of the individual applications available. You create or login to your creative cloud account and then enter your credit card details. Now for every month that you want to use the apps, you will be billed. If you no longer want to use it, you can cancel anytime.
In some countries you cannot go by the monthly payment method. You have to buy in blocks of one year. In this case the same applies as the above except that a reseller will purchase the license and assign it to your account. You can then apply the license to whatever email address you like. At the end of the time period, the program will stop working until renewed.
Initially there was a lot of resistance to the subscription model when it came to software. Now, most users have realized that they can use what used to be very expensive software, for even short periods of time. It is a model that will eventually be used by the majority of software makers. It is a win for both developers and consumers.