In Judaism, confession (Hebrew: וִדּוּי, romanized: vīddūy) is a step in the process of atonement during which a Jew admits to committing a sin before God. In sins between a Jew and God, the confession must be done without others present (The Talmud calls confession in front of another a show of disrespect). On the other hand, confession of sins done to another person may be done publicly, and in fact Maimonides calls such confession "immensely praiseworthy".
The confession of a sin in itself does not bring immediate forgiveness. Rather, it is one component of repentance in Judaism, which can lead to forgiveness.