There are a majority of shortcuts exclusive to Photoshop, such as;
CTRL+G activates the grouping function. This allows you to group pixels together and move them around as if they were one.
CTRL+I selects the eraser. Self explanatory,
CTRL+R toggles the ruler, a small bar on top of the canvas that can show inches, centimeters, and picas, among other ways of measuring sizes.
CTRL+H toggles the pixel grid, useful for extremely close-up photo manipulation.
CTRL+J copies layers. Simple enough.
CTRL+K opens the preferences window.
CTRL+W closes Photoshop.
CTRL+Q quits Photoshop.
CTRL+L opens the levels window.
CTRL+1 and +0 zoom in and out, respectively
2. The myth of the Tree Octopus has been officially debunked.
This is the closest I could remove the octopus from the tree before
turning it into calamari...
I used the magic eraser tool to remove the branches, than used the rest of the leaves using a basic eraser, shrinking it until I could see the pixels of the octopus. This is very intricate, and required much undoing if I made a mistake.