problem on uploading the program

Aim is to just upload a short program to check for its workability for the brushless motor.But the prog is not uploading. N repeatedly showing this msg

Arduino: 1.6.12 (Windows 10), Board: "Arduino/Genuino Uno"
C:\Users\ASUS\AppData\Local\Temp\untitled476662802.tmp\sketch_feb05a\sketch_feb05a.ino:1:55: fatal error: servo.h: No such file or directory
#include <servo.h>//Using servo library to control ESC
** ^**
compilation terminated.
exit status 1
Error compiling for board Arduino/Genuino Uno.

Have you #included the Servo library correctly I wonder ...

The Servo class is defined in Servo.h, NOT in servo.h.