A file with the .IDX file extension might be a Movie Subtitle file used with videos to hold the text that should be displayed in the subtitles.
Otu faịlụ nwere ndọtị faịlụ .IDX nwere ike ịbụ faịlụ Nkọwapụta DVD nke ejiri vidio jide ihe ederede nke a ga-egosipụta na ndepụta okwu.