Are there specific considerations or differences in encoding special characters like umlauts when using PHP on different server environments, such as IIS?

When encoding special characters like umlauts in PHP, it is important to consider the server environment and its default character encoding settings. For example, if using IIS, the server may have a different default character encoding compared to other environments like Apache. To ensure consistent encoding of special characters, it is recommended to explicitly set the character encoding in your PHP script using the `header()` function.

header('Content-Type: text/html; charset=UTF-8');