Google has posted some of the shortcuts that you can use while browsing Google Maps. With your mouse, you can zoom in and out: double left-click to zoom in on the area you're clicking, and double right-click (also known as Ctrl+Click for Mac users) to zoom out. If your mouse has a scroll wheel, you can also use that to zoom in and out.
You can also zoom in and out with the “+” and “-“ keys. There are some other keyboard shortcuts: with the arrow keys, you can pan left, right, up, and down with each respective arrow. Using the arrows moves the map just a tad, so to pan wider you can use the Page Up, Page Down, Home, and End keys to move north, south, east and west, respectively. Holding down any of these keys will keep the map scrolling across your screen.
Street View also has some useful keyboard shortcuts. To pan left in an image, use the left arrow or “A” key; to pan right, use the right arrow or “D” key. The up arrow moves you forward down a street, and the down arrow will put you in reverse and move you backward. When you want to see the top of a skyscraper or a mountain peak, you can use the Page Up or “W” key; to pan back down or check out our ground-filling, use the Page Down or “S” key. And the same tip of using the “+” and “-“ keys to zoom in and out also applies.