a skilled technician carefully examines the inside of an open desktop computer with a magnifying glass and small flashlight. She points to a specific component while holding diagnostic tools in her other hand. The computer screen shows error symbols and warning indicators that need attention. Step by step, she replaces a faulty circuit board with a new one from her toolkit. A customer watches hopefully from behind as sparks of electricity show the repair process working. The computer screen begins displaying normal startup messages as the problem gets resolved. someone identifying and solving problems in a technical system