Some info about Bluetooth will (hopefully) be posted here!
Bluetooth Core Specification
currently at V 4.2
GATT
Look at this as a Storage room with filing cabinets. The room is the GATT profile, The filing cabinets are the Services and the Dravers are the Charactheristics. Some of the drawers might have locks to restrict access.
Services
Services are predefined by Bluetooth SIG and can be found here.[1]
Charactheristics
“A characteristic is a value used in a service along with properties and configuration information about how the value is accessed and information about how the value is displayed or represented.”
A Charactheristic where a value, and information about the value, is stored in a Service.
A service is a collection of information, some of theese are predefined by the Bluetooth SIG. These services are meant as a tool to get compatabillity accross devices. If none are of your liking, make your own.
Abbreviations and expressions
GATT Generic Attribute Profile GAP Generic Access Profile UUID Universally Unique ID