How to open NEF files on Photoshop?

How can I open NEF files on Photoshop?

I bought a second hand Nikon D5000 + Sigma 70-300mm DG Macro (no OS no APO) last January 17, 2011; and I want to know how many shots had been made on it. So far, I have made less than a thousand shots on it.

Here are my shots of the Dinagyang Festival, last January 22-23.
http://www.facebook.com/...3396667125

NEF files are opened first in Adobe Illustrator until you make final adjustments to them for exposure and other elements. Once this is done, Photoshop will open them. The reason they won't open first in photoshop is because the color information has been stored separately.

As part of the Photoshop suite, you should have Adobe Camera Raw - it may need to be upgraded, but when you open a raw file in Photoshop it's Camera Raw that opens it for starters.

The camera may be too new for your version of Photoshop. When Adobe releases a new PS version they stop updating the Raw Converter.

You need CS4 or higher for the Nikon D5000.

How can i open NEF file to CS6 photoshop from nikon D3300 dslr cam since Im a beginner for this cam