The author identifies himself as Jude brother of James. Both Jude and James were half-brothers of Jesus. It is unknown whether this letter was intended for a specific church.
The purpose of this letter was to warn believers against false teachers. In his arguments, Jude often referred to the Old Testament. This may suggest that Jude was writing to a Jewish Christian audience. This letter has content that is similar to 2 Peter. They both speak about angels, Sodom and Gomorrah, and false teachers.
Translators may choose to call this book by its traditional title, "Jude." Or they may choose a clearer title, such as "The Letter from Jude" or "The Letter Jude Wrote." Jude is the same name as Judah or Judas. (See: [[rc://en/ta/man/translate/translate-names]])
It is possible that the people Jude spoke against were those who would eventually become known as Gnostics. These teachers distorted the teachings of scripture for their own gain. They lived in immoral ways and taught others to do the same.