Mobile Virtual Network Operators (MVNOs) are companies that provide mobile phone services without owning the physical network infrastructure. Instead, they lease network access from established Mobile Network Operators (MNOs) like Verizon or AT&T. This allows MVNOs to offer their own plans and pricing while relying on the MNOs' networks for coverage. MVNOs often target specific customer segments, such as budget-conscious users or niche markets. They can provide competitive pricing and unique services, making them an attractive option for consumers looking for alternatives to traditional carriers.