Let's learn how to create TUX in photoshop.
Step 1:
Start a new document of size 200x200 pix.
Draw a elipse using the eliptical marquee tool and fill it with black colour.
Create another layer and draw a elipse and fill it with white gradient
refer
this on how to fill the gradient)
Step 2:
Let's create the lower part of the body
Create another layer
and draw a new elipse like this

Fill it with white colour
Now this step is a bit tricky
Now deselect the selected elipse and draw another elipse on it like this

Now select Image inverse i.e Select>Inverse and press the delete key on the keyboard and we have this
Step 3:
Let's draw it's eye's now.
again create a new layer and draw an elipse for eyes.

duplicate layer for the other eye.
Step 4:
Let's create it's beaks
Again create a new layer and draw rectangle with the rectangle marquee tool.

Use the following gradient settings and fill the rectangle

Now select the free transform ( Edit>transform>prespective ) to make it as a triangle.

drop some shadow to give a little depth.
Step 5:
Let's create it's feet's now
Create another layer and draw a elipse like we did all these time.

Duplicate the layer to make another leg.

dat's all our cute little penguin is ready.
Hope you liked the tutorial.