SaaS Benefits and Subscription Licensing

What is the difference between perpetual on-premises, subscription and SaaS licensing models? What are the benefits of SaaS, Software-as-a-Service? OPEX, CAPEX and all that jazz.

ESSENTIAL READING

🟢 What is a license: https://samexpert.com/what-is-a-software-license-how-microsoft-licensing-works/