One of the big draws of flight simulation for students is that time spent in the simulator can often be counted towards earning a specific license or certification. How much time will count towards a specific regulation varies widely with the level of simulator and the local civil aviation authority (eg FAA or EASA.) simulators. For example a US pilot may apply 20 hours out of 40 required to meet the minimum time requirement for obtaining instrument rating. Cost is also a motivator to use simulation. In the above scenario overall training cost is reduced with the end product, a better and more proficient pilot. Unfortunately an airplane is a poor classroom.
Further, in learning to operate to the required level of proficiency most students, before the introduction of digital technology substantially exceeded the minimum hour requirements for their desired certifications. For example, an instrument rating 15 years ago typically took 70 hours in the aircraft to be proficient. Since that time and with the introduction of high technology AATDs, that number has been reduced to 52. This results in a genuine cost reduction for the student.
It would not be beneficial to provide a list of what levels of simulator can be used for how many hours towards what certification globally because it would simply be too complex. At the very least there are over 150 Civil Aviation Authorities around the world. Most define at least 5 levels of simulation, and administer at least 5 major certifications. However it's not as simple as just looking up 1,500 specifications, because each of those specifications changes quite frequently, and the official documents are often very complex. Furthermore in many jurisdictions the official schedules can be overridden by special policy decisions or on the authorization of an inspector from the local authority. As an example of these complexities suffice it to say the FAA regulation 14 CFR part 60 consolidated version with its attachments and appendixes is well over 300 pages with each page in the narrative having 4 columns.
We have covered the FAA, and EASA, information with there own pages however, even that changes frequently and is quite nuanced. As for your local authority we recommend contacting them directly. If you operate in a jurisdiction not covered by the FAA, or EASA we would be happy to work with you in determining requirements if you wish to purchase a simulator.