The reason why solar energy is so expensive is because of the raw materials that is used within the manufacturing course of. Platform-as-a-Service (PaaS) is the following layer up – in addition to the underlying storage, networking, and virtual servers this will also include the tools and software program that developers have to construct purposes on prime of: that would include middleware, database management, operating systems, and development tools. Authentication mechanisms: There are numerous methods customers can prove their identities to realize entry to programs or programs. These are known as authentication mechanisms and sometimes embrace one thing a consumer knows — like a password and consumer ID — or one thing a person has — like a token or a device with a recognized IP tackle.