Nearly every product has some data that it needs to ensure is available across restarts of the device, even if power is lost. On microcontrollers, flash memory is typically used for this non-volatile storage (NVS) memory. The same flash memory that holds the code of your application also stores the data your application uses and the data it creates. Here are some kinds of data your application might store:
Read-only data, such as the images that make up the user interface of your product or files containing static web pages ...
