There are actually 3 types of colours that one will need to know in order to use Photoshop to its potential.
The first is called RGB colour. RGB stands for red, green, and blue. RGB color is created by objects reflecting elements of red, green, and blue light and, technically speaking, it is the colour that we see in everyday life. It is also the colour that your television and computer monitor use to project images and therefore it is the type of colour most often used in Photoshop images on the screen.
The second type of colour, CMYK colour, is composed of cyan, magenta, yellow and black. With colours created in CMYK, the cyan, magenta, yellow and black are added in different degrees to achieve the desired shades. These are the colours used in the printing process. The 4 ink colours are combined to produce the desired shade.
The third type of colour is grayscale. Many people call these images "black and white" although the graphic term is grayscale because the image is actually made up of 256 shades of gray.
CMYK colours can do a pretty good job of reproducing most RGB colours, but not all. That's why the banana that you print out will never look exactly the same as the banana that you hold in your hand.
In general, use images in RGB mode if your final product will be displayed on the Web or on a computer screen. However, if your final product will be printed, it's best to use CMYK mode in order to see your image accurately.
To convert image to CMYK : Image->Mode->CMYK
To convert image to RGB: Image->Mode->RGB
Colour Settings, Lesson 4-2
Paint Bucket Tool can set opacity and tolerance level.
Rotate - Edit->Transform Path->Rotate
Move - Move tool
Delete - Delete key
Scale - Edit->Transform Path->Scale
Skew - Edit->Transform Path->Skew
Distort - Edit->Transform Path->Distort
One can use the Skew or Distort command to make the selection look squished or elongated. The Skew command works along a single axis, the Distort command works independently of either axis.
