Function as a service is a cloud computing service model for developing and running program code. The service provider provides developers with a cloud environment in which they can create modular components from written pieces of code and run the modules as needed.
The FaaS model allows developers not only to use the cloud environment to test the written code, but also to provide finished program modules for client use. This approach to developing software applications using modular components is called “Microservice Architecture” or microservices. In particular, it allows developers to modify small parts of code and easily integrate them into the application. When creating monolithic application architecture, any changes may create the risk of disrupting the entire system. Microservice architecture avoids this risk.
The FaaS model of cloud resources provision is alternatively known as Serverless computing. Formally, physical servers that host the cloud environment certainly exist, but developers do not need to worry about hardware maintenance and service, control performance and storage size. All the issues of ensuring the uptime, reliability and stability of the cloud environment fall on the provider. In addition, computing resources and storage size in the cloud are scaled automatically, i.e. developers get as many resources as they need for full-fledged work.