In this recipe, we will learn how to use std::span, which is a new feature coming with C++20. This recipe is important as std::span is a descendant of the Guideline Support Library's gsl::span, which is a core component of the library used to ensure that your C++ is Core Guideline-compliant. In this recipe, we will not only introduce std::span, but we will also explain how to use it in your own code and why it helps to encapsulate an array with its size as well as provide a convenient API for working with arrays in general.