Payment gateway providers are companies that offer secure platforms to process online transactions between customers and merchants. They act as intermediaries, encrypting and transmitting payment data from a website or app to the acquiring bank and ensuring the funds are transferred securely. These providers support various payment methods, including credit cards, debit cards, and digital wallets. Popular examples include PayPal, Stripe, and Square. Payment gateway providers play a critical role in e-commerce, enabling seamless, secure, and efficient payment experiences for businesses and customers.