Security is a crucial aspect of building applications. Web services usually expose information to third-party clients and companies; therefore, it is vital to avoid leaking data. The security layer of a web service is often a tedious part of the development process because it is hard to test and to verify. 

Security is important even for web services that are published in the internal network of the company, which, by default, is not accessible from the outside. As software engineers, we should do as much as possible to guarantee a strong level of security when we release a web service. It is also essential to understand that securing a web service is necessary to identify the consumers of your data and to prevent overuse of your web service. The next section will start by describing HTTPS and how to secure your data using HTTPS in a ASP.NET Core web service.