The world of commerce has expanded significantly in recent years. Specifically, developments in digital technology have opened up robust, efficient, safe, and convenient ways of conducting transactions. At the centre of this revolution lie payment processing platforms.

Payment processing platforms can be defined as third-party services or applications tasked with handling transactions between the payers (customers) and the payees (merchants). They provide a secure path and act as an intermediary to transfer funds from customers' accounts to merchants' accounts. Crucial for business transactions, they make purchasing and selling a seamless process for both parties involved.

In essence, when consumers make a payment for a product or service, the payment processor immediately carries out a series of tasks to process the transaction—starting from the point of sale to the depositing of funds into the merchant's account.

Various types of payment processing platforms are available in the global market. Some focus on integrating directly into a vendor's website (e.g., Stripe), others anchor on ease of mobile payments (e.g., Square), whilst some cater to large-scale business to business (B2B) transactions (e.g., PayPal).

In the realm of e-commerce, these platforms indispensably create an integrated shopping experience. Payment processors are responsible for instantly verifying transactions, checking the funds in a customer’s account, and approving (or denying) the transfer of funds. When purchasing online, customers can feel safe and businesses can trust that payment will be received.

Moreover, payment processing platforms have also helped businesses expand marketing efforts, by providing the analytical insights gained from tracking customer expenditure patterns. Platforms nowadays offer APIs (Application Programming Interface), which allows the seamless integration of payment systems into existing company websites, offering different options like credit/debit cards or mobile wallets.

In conclusion, as digital commerce continues to evolve, payment processing platforms will play an increasingly significant role in redefining the way business transactions occur. They not only make the transaction process more manageable, efficient, safe, and user-friendly but also pave the way for businesses to expand and conquer the global market. By opting for a reliable, third-party payment processor, businesses can avoid the technical hassles of setting up a system of their own, and can focus on the core parts of their enterprise. Customers, similarly, benefit from swift, safe, and easy payment methods. As such, the importance of these platforms cannot be understated and we can only anticipate their continued evolution.