The volume has went off on my tv. its a samsung le26b450c4w

First verify that the mute is disengaged (toggle the mute button). Second, check the sound configuration to make sure the internal speakers are on, or check the sound output to make sure it is going to the inputs of an external audio amplifier (stereo receiver) and that the external amplifier is working. Try a different input source - perhaps the problem is your cable feed or DVD player.
If the internal speakers are on, the volume is up, and you still don't get any sound from a known-good source (TV channel, DVD player, etc.), then try running the sound to a stereo system as described above.
If that works, you may have a shorted speaker amplifier (depending on the set's design, this may blow a fuse supplying power to both left and right amplifiers or a speaker protection circuit will keep the speakers disconnected). These aren't usually hard to repair, but if you find a blown fuse, fix the amplifier before replacing the fuse or you'll just waste another fuse.