There's been so much talk about Software-as-a-Service (SaaS) in recent years that stalwarts Platform-as-a-Service and Infrastructure-as-a-Service rarely get a look in.
Whilst Salesforce.com, arguably the first true SaaS product built from the ground up, gets much of the attention as the most successful company within one of the trio of concepts, spare a thought for the platform and infrastructure guys as they continue to grow and, indeed, often baffle technicians as to their true definition.
This handy infographic from ProfitBricks may help: