Top payment gateway platforms are services that securely process online payments by transferring transaction data between customers, merchants, and banks, enabling safe digital commerce and faster payment experiences; platforms like PayPal, Stripe, Razorpay, Square, and Authorize.Net differ in supported payment methods, security, developer tools, and transaction fees, as Stripe emphasizes API flexibility while PayPal focuses on global trust and ease of use, so you should choose the top gateway based on business size, technical requirements, and target customers.