Definition - What does Electromagnetic Shielding (EM Shielding) mean?
Electromagnetic shielding involves the use of a specialized material to block out certain types of electromagnetic fields or waves. Many types of consumer products feature electromagnetic shielding, either to keep certain kinds of electromagnetic waves inside a space or to keep them out of an internal area.
Techopedia explains Electromagnetic Shielding (EM Shielding)
A common type of electromagnetic shielding is called radio frequency identification (RFID) shielding. This system seals out radio waves in order to protect an internal area from wireless signals or requests for information that are conducted over radio frequency waves.
Many different types of electromagnetic shielding can be made from simple items like aluminum foil. Common examples of electromagnetic shielding include the interior of a microwave oven, which keeps radiation in, and shielded cabling, which also contains electromagnetic fields. Other kinds of electromagnetic shielding are sometimes called Faraday cages. These systems, such as the RFID-blocking tool mentioned above, block out electromagnetic fields from an interior space.