Starting with OS X 10.7, Apple changed its method for resizing windows. In the Classic Mac OS and through the first six releases of OS X, you had to resize windows using the tab at the bottom-right of the window; however, with OS X Lion Apple changed this behavior to give resizing controls along all edges of application and document windows.
What this means is in most cases, instead of having to move the left and top sides of a window to a desired location and then resize the rest accordingly, you can simply resize from the left, from the top, or any corner of these edges to move your window around.
This approach is far more convenient, but in addition to this behavior you can use several quick and easy modifications to enhance your window resizing efforts.
The first options are perhaps the obvious ones, where if you want to view content in full screen then you can activate this by clicking the double-arrow button in the upper-right corner of each window that supports it, or by pressing a relevant hot key (such as Control-Command-F for Finder windows).
The second option is to resize a window to fit its content, which is done by clicking the green "Zoom" button next to the red and yellow ones for closing and minimizing windows. Unfortunately the button's functions are not always consistent between programs, which makes it a touch unreliable; however, you can use some third-party enhancement programs such as Moom ($9.99 from the App Store) to give you options such as zooming a window to a specific section of the screen.
The next options are built-in enhancements to the resizing behaviors for windows. While you might find yourself resizing windows by moving the left side, then the right, and then the top and bottom (or perhaps combining these in part by using corner controls), there are a few ways you can speed this up, by using modifier keys along with your window resizing actions. For example, if you drag the right edge of a window while holding the Option key down, you will perform a mirror action to the opposite edge, in essence leaving the window centered but widening or reducing its overall width.
The two modifier keys that will alter the window resizing behavior are the following:
- Option: Holding this will mirror your resizing action to the opposite window control, resizing the window around its center.
- Shift: Holding this will preserve the aspect ratio of the window with respect to the opposite window control.
These two keys can be used in combination as well, so holding both will preserve the aspect ratio of the window while resizing around its center point.
With these options you can easily manage the each of the windows on your screen without always having to access each side or corner separately.