How do famous YouTuber's play Minecraft with no lag whatsoever?

I don't really understand WHY Minecraft lags on MY computer, It's a 1000 dollar computer that can play World of Warcraft on Ultra graphics settings with no lag whatsoever.

I have:
Processor: Intel(R) Core(TM) i7-4700MQ CPU @ 2.40GHz 2.40GHz
Installed memory (RAM): 8.00 GB
System type: 64-bit Operating system, x64-based processor
Memory: 648 GB free of 891 GB (C.
and 22 GB free of 24.9 GB (D.

Added (1). I even play with Optifine and low settings, but I still get 5-40 FPS (40 being if it doesn't involve moving or anything)

Added (2). Graphics Card: Intel(R) HD Graphics 4600

Celestic 14.05.2015

You're gonna need a better CPU, and possibly a GPU

johan 15.05.2015

More gpu. Maybe CPU. If you are using the internal graphics, no wonder why your frame rate is poor.

TBK 15.05.2015

Is your java version up to date?
Do you have 64-bit java?
Are your video card drivers up to date?

For best performance, make sure your settings are just like this:

Graphics: Fast
Smooth Lighting: Off
3D Anaglyph: Off
Particles: Minimal
Fullscreen: Off (turning it on MIGHT boost FPS)
Render Distance: 2-4 chunks
Performance: Unlimited
Advanced OpenGL: On
Clouds: Off
Use VSync: Off
Use VBOs: On

When using vanilla minecraft (no mods) don't use too much RAM!
I find 768MB of RAM to be optimal without mods.

Charlie 15.05.2015