If you don't want to hear the shutter sound when you take photos, then there are a few things you can try.
Firstly, some countries have laws to force the phone to play these sounds. Assuming you're not in one of these countries, then the first thing you can try is to go to the Camera App - Settings - Shutter Sound - Off.
If that doesn't work, then you can try turning the volume of the phone down or put it in silent mode when taking photos.
The last option is to Root your phone. If you don't know what that means, then it's best not to attempt it unless you have thoroughly read about the process. Once Rooted, go to this folder on your phone: /system/media/audio/ui and rename the camerashutter and/or cameraclick OGG files to something else.
Alternatively, on a rooted phone you can use a Root Browser, to edit /system/csc/feature.xml and set the option to TRUE. Then you should be able to go to Camera App - Settings - Shutter Sound - Off.