The technical rehearsal or tech rehearsal is a rehearsal that focuses on the technological aspects of the performance, in theatrical, musical, and filmed entertainment. It involves integrating lighting, sound, set changes, special effects, and other technical elements with the performance. Technical rehearsals generally happen after performers have learned their lines, blocking, and choreography. This lets the production staff, including directors, stage managers, lighting designers, sound engineers, and backstage crew, identify and fix potential issues. The forms of technical rehearsals range from a "dry tech"(without performers) to a "wet tech"(performers participate fully in costumes). Technical rehearsals are important for ensuring the safety of the performers, maintaining timing, and giving a professional experience for the audience during the main show.