This is a unique alphanumeric string, likely an internal asset ID or a reference to a source platform (such as a YouTube video ID or a stock footage identifier).
Right-click, select Get Info , and look at the More Info section. K02R6MTk_480p_AdobeExpress.mp4
Since this appears to be a personal or project-specific file, you can perform your own "deep review" using these methods: This is a unique alphanumeric string, likely an