ເບິ່ງຊອຣ໌ສສຳລັບ ມີເດຍວິກິ:Wikieditor-toolbar-file-alt-help

You can use this optional field to write a text description for people who cannot see the file.
The description should be enough for them to understand the purpose and information given by the media item. This is vital for blind users and other people using screen-reader software or text-only browsers.