Snapchat is a picture and video messaging application for mobile devices that allows users to send and receive messages that become unavailable after being read. Snapchat also features text chat functionality that allows users to send messages back and forth that don't become unavailable in the same way that photo and video messages do.
One of Snapchat's main points of appeal is the private nature of the messages sent over its network. Snapchat messages can be set to be viewable for varying lengths of time between 1 second and 30 seconds, after which the message can never be seen or opened again. The user receiving a message is able to capture a screenshot of a Snapchat message using other applications or functionality of his mobile device's operating system, but the sender is alerted when this happens. Each user receives a Snapchat score, which is generated based on the number of messages sent and received by the user.
Snapchat features a mass-messaging function known as stories that can be opened an unlimited number of times over a 24-hour period by anyone who receives them. When more than one story message is sent, they are compiled so that friends and recipients can view them back-to-back in the order in which they were generated.