A NOMEDIA (.nomedia) file is an empty text file usually found on Android devices or external storage cards. It is used to indicate that a folder do not contain multimedia files. This prompts multimedia players and gallery apps to skip scanning those folders for media files. NOMEDIA files have the .nomedia extension and are useful for various purposes.
By placing a NOMEDIA file in a folder, sensitive photos within that folder can be excluded from appearing in the Gallery app. They can also improve the performance of multimedia-viewing apps by excluding folders with a large number of media files from their searches, enabling faster loading of other multimedia content.
NOMEDIA files are recognized by many Android audio players, video players, and image browsers. Some apps even create their own NOMEDIA files to hide certain media files, like ads, from multimedia apps.