So I was tryna learn push button on my uno r3 (cheap clone) and i somehow ended up connecting the 3.3V pin to both ground and an input pin (pin 2) at the same time (Might've also disconnected and reconnected the input pin multiple times) . Very soon, I hear a spark and see smoke coming from the board ("magic smoke" or so I've heard). So I disconnect the usb and this "U5" component seems to be disfigured a bit. Now if I plug the usb back in, this region gets heated up quickly enough to burn my finger. Is my board salvageable by any means or do I require a new board?
Photo of thing that got hot?
Which one?
One in the middle?
Or near the USB port?
I noticed that the crystal on that clone is a 12MHz one. The standard crystal should be a 16MHz one.
So when you get a new one get one with a good crystal otherwise you will have trouble selecting baud rates for serial communications when you get further with your adventures in Arduino land.
That 12 MHz is for the CH340.
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I suppose that you could desolder all the components.
@shannoxx
If you mean U5, then you could desolder it and see if the board still works.
If you have a pair of small wire cutters, you could try cutting it off.
It happens to the best of us. 
If the Arduino is going to be your hobby, it's not a bad idea to buy an extra one. I try to keep extras of everything (everything that I have) but most components are a lot cheaper than an Arduino.
Personally, I wouldn't try to repair it unless I knew exactly what was wrong, and if I knew there was only one thing wrong. Often when something "blows" it takes other parts with it.
The most common ways of damaging a board are -
-Over voltage... i.e. Connecting 12V to the 5V pin.
-Static discharge (which is also over-voltage).
-Connecting a power supply or battery backwards.
-Shorts... i.e. Connecting a power rail to ground or to another-different power connection, or connecting an output pin to power or ground. This creates excess current.
-Other things that cause excess current (like connecting an 8-Ohm speaker to an output pin.)
I have a "dead Uno" that died for unknown reasons. So I assume it was static discharge. I wrote "BAD" on it and I keep it for a physical example if I want to check the dimensions or mounting holes, or just to see how it's going to fit in a box, or something. And it's a reminder to "be careful". And I keep a spare good one around.
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Equipment ruined varies directly with experience. 
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When I shorted a small signal diode across a power supply it went with a flash and a bang. My wife referred to it as a temporarily light emitting diode. 
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The blown part is the 3.3volt regulator.
It's only used by the Uno for switching off USB supply when on external power.
If you only use the Uno on USB power, then it should still work normally.
The 3.3volt pin is not used in most projects.
Leo..
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I think there is even a thread about those things here.
Smoke emitting diodes.
Sorry i meant U5
Yea, sorry, i meant U5, could you tell me what that is and any chance the board will work without it?
Its the U5 that seems blown and it gets really hot when i plug it into the USB port
So the blown part still gets hot?
Crush the plastic part with something (screwdriver, pliers).
Leo..
It's the 3.3V regulator.
There is a chance it may still work but you won't have 3.3V output anymore
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So i can just replace it? Thanks a lot
So i can still use the board but that component gets hella hot, so do i remove it?