Fixed typo in README

README.md

@@ -1,6 +1,6 @@
 # ORSSerialPort 
 
-ORSSerialPort is an easy-to-use Objective-C serial port library for OS X. It is useful for programmers writing Objective-C or Swift Mac apps that communicate with external devices through a serial port (most commonly RS-232). You can use ORSSerialPort to write apps that connect to Ardino projects, robots, data acquisition devices, ham radios, and all kinds of other devices. Using ORSSerialPort to open a port and send data can be as simple as this:
+ORSSerialPort is an easy-to-use Objective-C serial port library for OS X. It is useful for programmers writing Objective-C or Swift Mac apps that communicate with external devices through a serial port (most commonly RS-232). You can use ORSSerialPort to write apps that connect to Arduino projects, robots, data acquisition devices, ham radios, and all kinds of other devices. Using ORSSerialPort to open a port and send data can be as simple as this:
 
 ```objective-c
 ORSSerialPort *serialPort = [ORSSerialPort serialPortWithPath:@"/dev/cu.KeySerial1"];