While horror movies create a long arc of suspense of fear for the next moment, a thriller takes up this thread more subtly. The thrill is in the foreground because you almost can guess the next scene, but have to wait for it to happen. The protagonist is usually a character who faces evil with fairly simple means and seemingly has no chance to escape the catastrophic situation.
If there is a conflict between the characters on the psychological level, it is a psychological thriller. Truth and fantasy interpenetrate the main character's point of view. The resolution of the events occurs unprepared and in a surprising way. Alfred Hitchcock is one of the most famous representatives of this genre.