Many software developers are familiar with realtime, but we believe that realtime concepts and user experiences are becoming increasingly important for less technical individuals to understand.

At Fanout, we power realtime APIs to instantly push data to endpoints — which can range from the actual endpoints of an API (the technical term) to external businesses or end users. We use the word in this post loosely to refer to any destination for data.

We’re here to share our experience with realtime. We’ll provide a definition and current examples, peer into the future of realtime, and try and shed some light on the eternal realtime vs. real-time vs. real time semantic debate.

The Simple Definition

Realtime refers to a synchronous, bi-directional communication channel between endpoints at a speed of less than 100ms.

We’ll break that down in plain(er) English:

• Synchronous means that both endpoints have access to data at the same time (not to be confused with sync/async programming).
• Bi-directional means that endpoints can send data in either direction.
• Endpoints are senders or receivers of data; they could be anything from an API endpoint that makes data available to a user chatting on their phone.
• 100ms is somewhat arbitrary; data cannot be delivered instantly — but under 100ms is pretty close, especially with respect to human perception. Robert Miller proved this in 1986.

An Example of a Realtime User Experience

A simple example of a realtime user experience is that of a chat app. In a chat app, you "immediately" (sub-100ms) see messages from the person (endpoint) you’re chatting with and can receive information about when they read your messages (synchronous, bi-directional).

Realtime vs. Request-Response

Web experiences are beginning to move from request-response experiences to live, realtime ones. Social feeds don’t require a refresh (a request) to update, and you don’t need to email documents as attachments that need to be downloaded (request) and sent back with edits (response) — you just use collaboration software that works in realtime.

More Realtime Experiences

Realtime user experiences are everywhere you look — especially where near-instant access to information is valuable. You’ll find realtime in:

• Collaboration: Realtime access to internal and external information from your team is becoming the norm. It’s accepted that a sales inquiry (data) can be instantaneously relayed from live chat on your website, into your customer service portal, and then into Slack.
• Finance: Stock tracking and bitcoin wallets require immediate access to information. Applications like high-frequency trading exist specifically because of the ability of certain parties to access and act on data faster than others.
• Events: Second-screen experiences for sports, including live betting with realtime odds updates, are becoming increasingly common.
• Crowdsourcing: Distributed collection, analysis, and dissemination of data from distributed endpoints (think reports from WeatherUnderground stations or from the traffic app Waze) is only valuable when it occurs in realtime.

Realtime in the Future

As we see it (and admittedly, we are a little biased), realtime is quickly becoming the new normal. Up-to-date information is expected by businesses and end users. Realtime is the natural complement to trends like:

Big Data

As the number of digitally connected businesses, experiences, and devices rises, so does the amount of data generated. Data becomes more valuable as the three Vs of a dataset (velocity, volume, and variety) increase — and realtime transmission is central to the velocity component.

In the past, companies benefitted from hoarding data, but increasingly, data is becoming most valuable when shared (and monetized). The companies that can aggregate and share the most data, as quickly as possible, will be successful.

Proliferation of APIs

Businesses sharing data are increasingly going to do so through APIs. Entire businesses are being built on APIs by platform providers like Twillio (they only have an API) or they are coming to comprise substantial portions of existing businesses (like Salesforce’s API).

An elegant end-user experience is increasingly the product of data that’s being moved through multiple APIs — and the number of APIs is only going to increase as they trend toward becoming less technical and more accessible and interoperable. The APIs that provide access to data or move it through their system as quickly as possible will rise over those that cannot.

Realtime vs. Real-time vs. Real Time

The endless debate — what’s the correct way to write what we’ve been discussing? We use realtime because we believe that “real time” refers to something experienced at normal speed and not condensed or sped up. For example, watching grass grow in ‘real time’ is not very exciting — but a time lapse is.

We also don’t like hyphenating – so we went with realtime instead of real-time (and it looks like most of the industry agrees with us).

This post originally appeared on the Fanout blog.