Notification glossary: Essential terms you need to know
TLDR: What is this notification glossary and who is it for?
This glossary is a starter kit for anyone new to building notification systems, especially product and engineering teams. It defines the core terms behind channels, push infrastructure, routing, events, analytics, and security. If you are evaluating or setting up Fyno, these definitions will help you plan, integrate, and troubleshoot faster.
Access and setup terms you will use first
These are the first concepts you touch when you wire any notification stack: how systems authenticate, and how providers connect. If you get these wrong, everything else becomes painful, from delivery failures to messy provider lock-in.
API key
An API (Application Programming Interface) key is a code used to identify and authenticate an application or user. It provides a secret token to help with authentication.
API keys allow software programs to communicate, share data, and integrate their functionalities. API keys can be used for user authentication and authorization depending on the product's nature.
You would need a notification API key at two levels:
To integrate Fyno with your provider (for example, Twilio)
To integrate your application with Fyno (to send notifications directly)
Integrations
Integrations are additions of service providers to your platform, so you can easily trigger notifications at your convenience.
It's quite tedious to integrate an API from every provider individually. It's far easier to use a tool that allows you to integrate multiple service providers to run different campaign parts for you. For example, you might need a different integration for SMS, a different one for WhatsApp or email, etc.
💡 Using a comms engine like Fyno also gives you the access to integrate multiple providers at once, thereby saving big on money as well as engineering effort.
💡 Using a comms engine like Fyno also gives you the access to integrate multiple providers at once, thereby saving big on money as well as engineering effort.
Channels and notification types
Channels are the “where” of delivery, while notification types describe the “how it shows up” to the user. This section helps you separate the message destination (SMS vs email vs push) from the experience (push vs in-app) so you can design better routing and measurement.
Channels
Communication vehicles that span SMS, email, instant messaging, voice, etc., with content that includes text, imagery, videos, gifs, and other such media.
Choosing the right channel for your communication is crucial. For example, something urgent could be sent via SMS so the user is immediately alerted, but something lower on priority could be sent via email.
Depending on the content of the notification, the appropriate channel should be chosen.
Push notifications
Pop-up messages from mobile apps on the user’s device, even if the app isn’t open. They’re two-pronged, can be on the web or mobile. However, mobile has proven to be far more effective than the web.
The primary reason to use push notifications is to get users’ attention to promotions, updates, reminders, etc. Essentially, a push notification has a title, body copy, the capability of attaching an image/video or a URL, and an instant CTA.
To understand how push notifications work, it’s important to know the technical mechanics behind their implementation, including the registration process with operating system services, the use of unique identifiers for targeted messaging, and the importance of user preferences.
There are various types of push notifications, such as mobile app push notifications, which can be single or double opt-in, and they can be personalized and segmented to enhance user engagement.
Push notifications are a powerful way to connect and reconnect with the end user. They help increase visibility and engagement, drive conversions, help retention, and scale businesses. Organizations create push notifications tailored to specific customer needs, highlighting their effectiveness in various industries such as finance, health, and hospitality.
Mobile push notifications
Messages sent directly to a user’s mobile device through apps. These notifications appear on the user’s home screen or notification centre, even when the app is not open.
Android users have unique control over notifications, such as setting priorities, grouping notifications, and managing how notifications appear. Mobile push can include text, images, videos, and interactive elements like buttons.
These notifications can be viewed directly from the lock screen, providing immediate access even when the user is not actively using the app. Properly implemented, mobile push notifications can significantly enhance user retention and drive app usage.
Rich push notifications
An advanced form of push notifications that include multimedia elements such as images, videos, GIFs, and interactive buttons.
These go beyond simple text alerts, allowing businesses to deliver more engaging and visually appealing messages. For example, a retail app might send a rich push notification with a clickable image of a new product, or a news app might include a video snippet of breaking news.
Including rich media can significantly increase the effectiveness of push notifications by capturing the user’s attention and encouraging interaction.
In-app notifications
Notifications that pop up while the user is active on the mobile app.
They differ from push in that in-app notifications guide the user within the app, while push brings the user to the app. Depending on the product's design aesthetics, these notifications can be full-screen or smaller overlays.
In-app notifications also help hold the user's attention but can be disturbing if overused. So, it's extremely important to selectively target, schedule, and notify users. The content can vary from asking users to rate the app, to consent prompts for push notifications, to guides on using the product better.
Web push technical components
Web push is powered by a few specific building blocks that are easy to mix up: a token-like identifier (subscription), a background script (service worker), and authentication keys (VAPID/server keys). If you are troubleshooting web push delivery, these terms are the ones you keep returning to.
Push token
A unique identifier assigned to a user's device or browser when they opt-in to receive push notifications from an application. This token acts as the address to which push notifications are sent.
Push tokens are generated and managed by the push notification service provider (e.g., Apple Push Notification Service for iOS devices, Firebase Cloud Messaging for Android). Managing and storing push tokens securely is crucial for maintaining the integrity of your notification system.
Push API
A web standard that enables web applications to receive push notifications from a server, even when the application is not active or open in the user’s browser.
This API works in conjunction with Service Workers, allowing notifications to be delivered asynchronously and displayed to the user in real-time.
Service worker
A script that runs in the background of your web application, allowing it to intercept network requests, cache resources, and handle push notifications even when the web page is not open.
It’s essential for enabling features like offline access and background syncs, making it a key component for delivering web push notifications.
Service-worker registration
The process of registering a service worker with your web application.
This registration allows the service worker to manage push subscriptions, ensuring that the application can receive and display notifications to the user anytime. It’s the first step in setting up push notifications on the web.
Notification payload
The data sent from the server to the client’s device or browser when triggering a push notification.
This payload includes all the information needed to display the notification, such as the title, body text, icon, and any action buttons. It’s the content that the user ultimately sees when they receive a notification.
VAPID (Voluntary Application Server Identification)
A protocol that provides a way to authenticate push messages sent from your server to the user’s browser.
It helps ensure that the push notifications are coming from a trusted source, enhancing the security of the communication between your server and the user’s device.
Server key
A unique credential your server uses to authenticate and send push notifications to users.
It ensures that the messages are securely delivered to the correct recipients, maintaining the integrity and reliability of your notification system.
Orchestration and system design terms
Once you have more than one provider or channel, notification complexity ramps up fast. Orchestration terms help you think in systems: how messages pick providers, how you reduce engineering toil, and how you keep delivery reliable under load.
Routing
Building an algorithm to determine the most appropriate service provider to service your notification request.
After integrating multiple providers into your system, how do you figure out which provider should trigger the notification and how?
That’s when routing comes into the picture. Just because you've integrated providers for different channels like SMS, email, WhatsApp, slack, etc, doesn't mean you need to use all of them simultaneously, and neither should one provider carry a heavy load. Routing acts as the load balancer.
Events
A superset that encapsulates templates, the channels it should engage, and the route or provider the notification should use.
This is handy if your notification ecosystem has become more complex, with more than 2 service providers or channels. Events are mainly designed to reduce engineers' workloads.
Campaign management and measurement
If you cannot measure notification performance, you will keep guessing. These terms help teams align on what “good” looks like, how you benchmark campaigns, and how you use data to improve segmentation, personalization, and channel selection.
Campaign reports
A way to understand how a campaign worked or didn’t so you can use insights to plan future projects.
Conversion analytics helps you set campaign benchmarks and determine how well your notifications perform.
Click through rate (CTR)
The percentage of users who click on a link within a notification compared to the total number of notifications sent.
It’s an essential indicator of how engaging and relevant your notifications are to your audience.
Delivery rate
The percentage of notifications that are successfully delivered to users' devices or browsers.
A high delivery rate indicates that your notification infrastructure is reliable, ensuring that your messages reach your audience as intended.
Subscriber acquisition report
Tracks the number of new users who have opted in to receive notifications over a specific period.
This report helps you understand the growth of your notification audience and the effectiveness of your strategies to attract and retain subscribers.
User profiling
Collecting and analyzing data about your users to create detailed profiles.
These profiles help you personalize notifications, making them more relevant and increasing the likelihood of engagement by delivering content that resonates with individual users.
Segmentation
Dividing your audience into distinct groups based on characteristics such as behaviour, demographics, or preferences.
By targeting notifications to specific segments, you can increase relevance and effectiveness, ensuring that each user group receives content tailored to their needs.
Security, privacy, and compliance terms
Notifications touch sensitive user data, and in many businesses, they also trigger regulated communications. These terms help you think clearly about confidentiality, user choice, and compliance obligations before you scale volume across channels.
Encryption
Converting notification data into a secure format that can only be read by the intended recipient.
This ensures that the content of your notifications remains confidential and protected from unauthorized access during transmission.
User keys
Unique identifiers used to encrypt and decrypt notification data for individual users.
They play a crucial role in maintaining the privacy and security of user information, ensuring that notifications are securely delivered and accessible only to the intended user.
Opt-in/opt-out management
Tracking and managing user preferences for receiving notifications.
This ensures that users have control over whether they receive notifications and that your notification practices comply with privacy regulations like GDPR.
Compliance considerations
The legal and regulatory requirements that govern how notifications are sent, such as GDPR in the European Union.
Ensuring compliance involves adhering to guidelines on user consent, data protection, and the secure handling of user information.
Advanced concepts that improve relevance and timing
Advanced concepts help you go from “messages sent” to “messages that matter.” They improve relevance (deep links, geo) and timeliness (TTL), which directly influences engagement, opt-outs, and long-term deliverability across channels.
Geo-tagging
Adding location data to notifications, allowing you to customize content based on where the user is located.
This can be used to send relevant location-based offers, alerts, or updates, enhancing the relevance and timeliness of your notifications.
Deep linking
Linking a notification directly to a specific page or section within an app.
This lets users quickly access relevant content or perform specific actions within the app, improving the overall user experience.
Time to live (TTL)
How long a notification remains valid after being sent.
If the notification is not delivered within this time frame, it will expire and not be sent to the user. Managing TTL is important for ensuring that notifications are timely and relevant.
How Fyno fits into this glossary
If you are using Fyno, these terms show up in day-to-day work in a very practical way:
API keys and integrations are how you connect providers and your product to Fyno.
Channels, routing, and events are how you decide what goes out, where, and through whom, without overloading one provider.
Reports and metrics are how you prove impact and improve campaigns.
Opt-in/opt-out and compliance are how you keep communication permissioned and scalable.
Conclusion
That’s broadly it, folks! Understanding each of these terms will give you an overarching view of a notification system and what makes it the smooth engine it is. We hope this was helpful.
Stay tuned for lots more from us very soon.