User notifications are messages or alerts that inform users about important updates or events related to an application or service. These notifications can appear on devices such as smartphones, tablets, or computers, and can include reminders, messages, or alerts about new content. They help keep users engaged and informed about activities or changes that may require their attention. Notifications can be categorized into different types, such as push notifications, which are sent directly to a user's device, and in-app notifications, which appear while using an application. Users often have the option to customize their notification settings, allowing them to choose which alerts they want to receive and how they want to be notified.