IRremote library doesn't work

Using Arduino Programming Questions
1

I have use follwing program. but it gives the error like

sketch_jan27a:3: error: 'IRSend' does not name a type

and i incuded IRremote file into library

#include<IRremote.h>
IRsend irsend

void setup()
{
Serial.begin(9600);
}

void loop()
{
if(Serial.read()!=-1)
{
for(int i=0; i<3; i++)
{
irsend.sendSony(0xa90,12);
delay(40);
}
}
}

2

and i incuded IRremote file into library

Which library folder did you put it in ?

3

I have uploaded into where it is installed-- Arduino-> libraries-> IRremote-> IRremote.h
and
Arduino-> libraries-> IRremote.h

both the places. but it doesn't work.

4

Arduino-> libraries-> IRremote-> IRremote.h

is that under Program Files ?

5

You must restart the Arduino IDE, after installing the library files.

6