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 # HomeSpan Library Reference
 
-*(coming soon)*
+The HomeSpan Library is invoked by including *HomeSpan.h* in your Arduino sketch as follows:
+
+```C++
+#include "HomeSpan.h";
+```
+
+At runtime this HomeSpan will create a global object named `homeSpan` that supports the following methods:
+
+* `void begin(Category catID, char *displayName, char *hostNameBase, char *modelName);` 
+  * begin() initializes homeSpan and **must** be called at the beginning of each sketch before any other HomeSpan functions.
+  * all arguments are **optional**
+  * *catID* - the HAP Category HomeSpan broadcasts for pairing to HomeKit.  Default is [Category::Lighting](Categories.md)
+  * *displayName* - the MDNS display name broadcast by HomeSpan.  Default is "HomeSpan Server"
+  * *hostNameBase* - the full MDNS host name is broadcast by HomeSpan as *hostNameBase-DeviceID*.local, where DeviceID is a unique 6-byte code generated automatically by HomeSpan.  Default is "HomeSpan"
+  * modelName - the HAP model name HomeSpan broadcasts for pairing to HomeKit.  Default is "HomeSpan-ESP32"
+