Wood block text
How to use it
Put a block of colour behind each letter of some text, with gaps between each block.
When to use it
This is very similar to putting one block of colour behind the whole piece of text, and it does the same thing: Adds contrast to the text, especially compared to the background. Using individual backgrounds for each letters gives the text a "wood block" feel, after the blocks that can be used to press ink into paper to create printed letters.
This technique is not very common, but aside from the stylistic choice, it can also let a little more background through the gaps between letters, meaning the text will feel more a part of the background.
What to watch out for
Having equal gaps between each block is much easier if you're using a monospace font, where each letter takes up the same amount of space. You might also want to use all capital letters, so that each letter fills its block better.