A cryptocurrency on-ramp refers to an exchange or similar service where you can offer fiat money in return for cryptocurrency.
For anyone to become involved in cryptocurrency, their first step will often be to simply buy some. This will require the trade of fiat money for digital assets, and any service that provides this is known as an “on-ramp” into cryptocurrency. On-ramps are a way for new users and new money to enter into this space, but not all of them act in the same way.
For example, one of the most common places for new users to get their first coin is an exchange. Not all exchanges allow direct fiat purchases, but many of the bigger names will, and more are integrating this feature all the time. In addition to regular exchanges, there are also over-the-counter, or OTC, markets. This is where users trade with each other directly at agreed-upon prices that may not match the exchange rate exactly. There are multiple platforms that can offer this, but the OTC realm is more for large purchases or sales and is more commonly used by institutional buyers. Both exchanges and OTC services often have APIs that can be integrated into other applications, which can then make trading across multiple markets easier for advanced users.
One last common on-ramp is cryptocurrency ATMs, where users can literally deposit cash and receive digital assets in return. Of course, these aren’t available in all cities yet, and there are usually limited assets being offered, so going this route may or may not be a hassle.