Subtitles
Jubler
Jubler is essentially a lightweight, easy-to-use editing software that enables users to synchronize subtitles with video files
Subtitle Workshop
Subtitle Workshop is typically the choice when subtitle files, which are initially simple text files, become harder to manage with elementary text editors
AegiSub
AegiSub is a simple handling program for subtitles
Subtitle Edit
Subtitle Edit can become your trusted assistant if you often deal with creating, syncing, or just editing subtitles