An electric steam iron is a common household appliance designed to remove wrinkles from fabric using a combination of heat, pressure, and steam. Its primary function is to apply these elements to cloth, relaxing the fibers and allowing them to settle into a smooth, flat position. The core of any electric steam iron is its soleplate, the flat, smooth surface that makes direct contact with the fabric. Traditionally made from aluminum or stainless steel, modern soleplates are often coated with advanced materials like ceramic or titanium for smoother gliding and scratch resistance. The soleplate is heated internally by an electric heating element, a coiled wire that converts electrical energy into heat when current passes through it. A thermostat within the iron regulates this temperature, allowing users to select settings appropriate for different fabric types, from delicate synthetics to sturdy cotton.

The steam generation system is what distinguishes an electric steam iron from a simple dry iron. A dedicated water reservoir, typically a removable plastic tank, is located within the iron's body. When the steam function is activated, a small amount of water is released from this reservoir onto a hot surface or into a steam chamber inside the iron. The intense heat instantly vaporizes the water, converting it into steam. This steam is then expelled through a series of tiny holes in the soleplate directly onto the fabric. The moisture from the steam helps to loosen tight wrinkles more effectively than dry heat alone. Many irons offer a burst of steam or a vertical steam function; the former injects a concentrated dose of steam for stubborn creases, while the latter allows the user to steam garments hanging on a hanger, which is useful for delicate items or freshening up clothes.

Safety and control features are integral to the design of an electric steam iron. An automatic shut-off function is a standard safety component, turning the iron off if it is left motionless on its soleplate or heel rest for a predetermined period. This prevents overheating and potential fire hazards. Controls are usually located on the handle or top of the body, including a dial or digital display for temperature, a steam output selector, and a button for spray mist, which sprays a fine water mist to dampen fabric for tougher wrinkles. The power cord is designed to swivel at its base to prevent tangling during use. Using an electric steam iron effectively involves understanding the fabric care labels, filling the reservoir with appropriate water, and allowing the iron to reach the selected temperature before beginning. This appliance combines thermal and mechanical engineering to perform a simple but essential task, making it a staple in home laundry care worldwide.