What the heck does this mean anyway?

I was doing a tutorial from a site that was listed on Pank's main page. Well, it's French and I had to use babelfish to translate. I just do not know what they mean by:
"and place a horizontal guide at 50 pixels and vertical in the same way"

The tutorial is found at here: http://www.piregwan.com/tutorials/bouton.php

It's nice. Too bad it's in French. -___-

Thanks for reading!

Click on the rulers on the edges of the image window you are working with, and drag into the image. A blue line will appear. That is a guide. It's just saying to set them at 50 pixels each.

(If you don't see the rulers, press CTRL + R)

Placing guides is easy. Hit ctrl+r to show the rulers if the are not visible. Next right click on the ruler to make sure the unit of the ruler is set to pixels. Click and drag the vertical ruler to create a guide. Drag it to the position 50. Do the same thing with the horizontal ruler. You are done! As your document is 100*100 pixels, the result should be to guides meeting at the middle of your document.

Hehehe - Looks like deker and I posted at the same time !

Ah, thanks! I was a little confused 'cos I got cm instead of pixels and didn't know I had to right-click to select pixels. =)

Hmmmz... the tutorial was kinda easy. Although I'm trying to figure out how he did the other blue-ish part of the circle. I'm guessing it's most likely select tool, inverse plus some magic wand. Then hue/saturation with colorize and hmmmz... maybe bevel/emboss? Not very sure though.

But thanks for your help anyway...