Year 2015 wasn’t that long ago. I was in my late teens, I should remember how things were. But honestly? It all feels like a blur. Those days of carrying cash to the store, buying Stationeries and Snacks — they almost play out in greyscale in my head. Wild, right? I’m not even that old — but UPI has completely flipped the script.

It’s convenient, clean, and everywhere. Just a couple of years ago, I was still carrying some cash to buy fruits from street vendors in my hometown, Salem — a tier 2 city. But not anymore. Now, nearly every vendor has a Paytm or PhonePe QR code hanging from their cart. If this isn’t a definition of success, I don’t know what is.

It’s slick, simple, secure (sorry Apple Pay, we’ve got 2FA too 😎). But behind the scenes, I know it’s a beast of a system.

As someone who’s tried to stay in the loop with Tech and and is trying to understand payments, I’ve realized — for something that looks super intuitive and obvious on the outside, there are quite a few terminologies that don’t land right away.

So, I’ve decided to stop assuming things and finally research how this whole system really works. Because let’s face it—just because we use something every day doesn’t mean we understand it.

If you’ve ever nodded along in a meeting or while reading a news article without truly getting what a “payment aggregator” or “issuer bank” is, this one’s for you.

Let’s begin with the terminologies—the building blocks. To make it easier, I’ve broken them down into five key sections:

1. Stakeholders

The people and institutions involved in the payments journey — consumers, merchants, banks (as issuers and acquirers), and platforms. Everyone plays a role in how money moves.

2. Players in the Payment Ecosystem

This category includes all the key entities that enable and support digital transactions in India — such as banks, payment gateways, payment aggregators, orchestrators, merchants, and end users.

3. Types of Payments

Outlines the various digital payment methods available in India, including UPI, card-based payments, digital wallets, net banking, BNPL, contactless card payments, and Aadhaar-enabled payments.

4. Payment Networks

Describes the infrastructure systems that facilitate the transfer of funds between payer and payee — starting with card networks like Visa, Mastercard, Amex, and RuPay; the NPCI‑operated platforms (e.g. UPI, IMPS, BBPS); and traditional bank transfer networks like NEFT and RTGS.

5. Authorizing & Regulatory Bodies

Institutions like the RBI—govern, regulate, and authorize the functioning and compliance of the digital payments ecosystem.