Computer output devices display processed data in readable form. Common output devices include computer monitors like CRT, LCD, and LED monitors which display visual information like text and graphics, LCD projectors, smart boards, and various types of printers like inkjet, laser, and thermal printers which produce hard copies of information. Speakers are also an output device used to play sound. Maintaining computers properly helps extend their life by installing antivirus software, performing regular updates and maintenance, backing up files, cleaning screens and vents, using surge protectors, avoiding temperature extremes, and transporting laptops in protective cases.