The article discusses the 'contains' function in Terraform, which checks if a specified value exists within a given list or set. It returns true if the value is found and false otherwise. The syntax of the function is contains(list, value). Practical examples using lists and strings are provided. The article also compares it to the strcontains function, which checks whether a substring is within another string. Both functions are useful for decision-making based on list or set contents and string manipulations respectively. Additionally, the article mentions Spacelift as a tool that makes working with Terraform easier by supporting Git workflows, policy as code, programmatic configuration, context sharing, drift detection, and more features.