An ever-growing repository of technical terms around realtime technology and beyond.

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Authentication is the process of verifying the identity of a user, server, app or device to proceed to log in to a system and access its resources.


Authorization is the process of granting permissions to a user, application, or server to access and modify resources on a system.


Business Associate Agreement (BAA)

BAA (Business Associate Agreement) is a contract between a HIPAA-covered entity (the organization who is delivering the product), and HIPAA business associates (the organization or vendor working with the entity to store, transmit, or process PHI).


Chat API

A Chat API is a collection of programmable building blocks that can be used to provide realtime chat features to an application or website.

Comet (Programming)

Comet is a web application design paradigm that describes a continuous, two-way interaction between a server and a web browser using native HTTP methods.


Fan-out (Software)

Fan-out is a messaging pattern where messages are broadcast in a one-to-many arrangement. A basic example of this pattern can be seen in the functionality of a Publish/Subscribe messaging system, as Pub/Sub implies the ability to route messages from a single sender to multiple receivers.


Geolocation API

The Geolocation API is a JavaScript scripting interface that makes it easy to retrieve the geographical location information stored on a device or web browser.



Health Insurance Portability and Accountability Act (HIPAA) ensures the protection and confidentiality of patient health information (PHI).

HTTP Streaming

HTTP Streaming is a push-style data transfer technique that allows a web server to continuously send data to a client over a single HTTP connection that remains open indefinitely.


HTTP/2 is the new version of HTTP (Hypertext Transfer Protocol), superseding HTTP/1.1 with several optimizations designed to improve the speed of web communications.


Infrastructure-as-a-Service (IaaS)

IaaS is a model of cloud computing in which all physical infrastructure to support a computing environment is provided by a third party.

IP Messaging

IP Messaging describes the general use of TCP/IP (the Internet protocol) to provide messaging capabilities to web and mobile applications.



JSON (JavaScript Object Notation) is an open standard messaging format used to exchange data between, and within, all types of web applications and servers.


Messaging API

Messaging API refers to any service that enables developers to implement messaging technologies in an application via a single programmable interface.


A microservice is a special form of SOA in which apps are built in terms of distinct modular services, each responsible for a specific function.



ngrok is a cross-platform application that enables developers to expose a local development server to the Internet with minimal effort.


PHI (Protected Health Information)

PHI (Protected Health Information) is a category of information that includes all individually-identifiable health information

Platform-as-a-Service (PaaS)

Platform-as-a-Service (PaaS) is a model of cloud computing where a ready-made computing environment is made available to developers to test and deploy apps.

Privacy Shield Certification

The Privacy Shield program is a data protection framework for US organizations who seek to become compliant with current European and/or Swiss privacy regulations regarding the transfer of EU residents' personal data to the US.

Publish-Subscribe (Pub/Sub)

Publish-Subscribe is a software design pattern that describes the flow of messages between applications, devices, or services in terms of a publisher-to-subscriber relationship.

Push Notification

A Push Notification is a type of notification that forces the display of a new message to the user's current interface. Depending on the application, these messages may either originate from a local application backend or remotely in the cloud.


Real Time Computing

Real time computing, or reactive computing, is a concept that describes any computing system that must respond to changes in the environment according to definite time constraints, usually on the order of milliseconds.

Real Time Data

Realtime data is any data that represents a recent change in an environment, whether the environment is physical (natural processes) or virtual (instant messaging, social media).

Real Time Messaging

Realtime messaging refers to the distribution and delivery of messages that are designed to be consumed or otherwise used in real time (i.e. as events occur and no later).


Serverless Compute

Serverless compute refers to the practice of running application code on servers that are provisioned as-needed by a third party cloud provider.

Smart Notification

Smart Notifications is a relatively new concept used to describe the various techniques designed to make realtime, push-style messaging (such as Push Notifications) more relevant, useful, and appropriate for individual users.

SMS (Short Message Service)

SMS (Short Message Service) is a way to send short, 160-character text messages from one mobile device to another over the cellular telephone network.

SOAP (Simple Object Access Protocol)

SOAP (Simple Object Access Protocol) is a messaging protocol that comprises a strict set of rules governing data transfer between clients and servers.


Socket.IO is a cross-browser JavaScript library that provides bidirectional, event-driven communication capabilities for use in realtime applications.

Software-as-a-Service (SaaS)

Software as a Service (SaaS) is a model of cloud computing in which complete applications are hosted in the cloud (i.e. on the Internet) and offered to consumers on-demand, usually via web browser.


Team Collaboration Tool

A team collaboration tool is any application that makes it easy for a group to work together on a common project in realtime.



A webhook is a technique used by a web application to send notifications to a specific, user-defined URL when something happens.


WebSocket is a transport protocol defined by a persistent, bidirectional communication channel between server and client that takes place over a single TCP socket connection.



XMPP (Extensible Messaging and Presence Protocol) is an open source, decentralized messaging protocol that was born from Jabber, an early realtime chat protocol.

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