For the longest time in Mac OS X windows were all resized the same way — via the little handle in the lower right hand corner of every window. In Lion though, this drastically changed. Now a user can resize a window from not only any corner, but even from any side.
Now I say this all as if it’s such a huge new life changing feature. It’s not, of course, but it’s still nice to have. It’s especially useful in instances where you have the width of a window just perfect, but you want to slightly alter the height (think Twitter, etc.). In Lion you can simply drag the bottom of the window down to do this.
What is more interesting than all of this though, and what is truly ‘new’ for an operating system, is that you can actually alter the way in which a window is resized by holding down certain keys on your keyboard while dragging with your mouse to resize a window.
Here are the various alterations now possible in Lion:
To really understand what all these do of course, I urge you to try it out for yourself, and remember them the next time you go to resize a window. It’s all rather useful.