How can checking the HTTP header "Content-Type: text/html; charset=utf-8" help troubleshoot issues related to character encoding in PHP applications?

When troubleshooting character encoding issues in PHP applications, checking the HTTP header "Content-Type: text/html; charset=utf-8" can help ensure that the correct character encoding is being used. This header specifies that the content is in HTML format and encoded in UTF-8, which is a widely supported character encoding that can handle various languages and special characters. By setting this header correctly, you can prevent issues such as garbled text or incorrect display of characters in your PHP application.

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