> For the complete documentation index, see [llms.txt](https://hasgeek.gitbook.io/50p-handbook/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://hasgeek.gitbook.io/50p-handbook/master.md).

# Introduction

HasGeek is pleased to present The 50p Payments Handbook, a compilation of articles from our blog with additional contributions from our partners and experts in the field.

For up-to-the-minute reading, please visit our blog, <https://blog.50p.in> and watch for events and meetups on <https://50p.in>

This handbook is supported by Instamojo and contains a sponsored interview with the founder of Instamojo. All views expressed in the handbook are the authors’ own. This handbook is continuously updated and revised. For a full list of changes, check out the [changelog](/50p-handbook/changelog.md).

You can always download this e-book for free in the format you want - [ePub](https://www.gitbook.com/download/epub/book/hasgeek/50p-handbook), [mobi](https://www.gitbook.com/download/mobi/book/hasgeek/50p-handbook) and [PDF](https://www.gitbook.com/download/pdf/book/hasgeek/50p-handbook).

## Table of contents

### UPI and the ecosystem

### [UPI ecosystem overview](/50p-handbook/upi-ecosystem-overview.md)

### [BharatQR](/50p-handbook/master.md#bharatqr)

### [UPI–BharatQR integration](/50p-handbook/upi-bharat-qr-integration.md)

### [BBPS - How it works](/50p-handbook/bbps-how-it-works.md)

### [Aadhaar and payments](/50p-handbook/aadhaar-and-payments.md)

### [Payments on WhatsApp? Here's how it works.](/50p-handbook/payments-on-whatsapp-heres-how-it-works.md)

### Cards and Electronic payments

### [Samsung Pay](/50p-handbook/samsung-pay.md)

### [Contactless payments](/50p-handbook/contactless-payments.md)

### Blockchain and cryptocurrencies

### [Demystifying ICOs](/50p-handbook/demystifying-icos.md)

### Policy, regulations, and security

### [Security in FinTech](/50p-handbook/security-in-fintech.md)

### [Building a payment product in India](https://github.com/hasgeek/50p-handbook/tree/b72e213bacf08e40b1ba8a8d9f49ee5658c58beb/building-a-payment-product-in-india.md)

### [Thoughts on PayTech business models in India](/50p-handbook/master.md#thoughts-on-paytech-business-models-in-india)

### [e-KYC workflows in FinTech and payment companies](/50p-handbook/master.md#e-kyc-workflows-in-fintech-and-payment-companies)