Otherwise, it's attractive, looking a lot like Aqua and MacOS X. Simple and clean, it's very easy to find your way around. It's divided into 5 major areas- Living, Buying, Building, Camera, and Game Options. When the cursor is moved over an icon, a description of that icon's function pops up. The Live mode is where the Sims come to life. In all other modes, time stops still.
Building is very easy.
Select a wall and simply drag it out. After a house is built you will see it's square footage. I have no idea how Maxis came up with this scale, but for your reference, a 10 square by 10 square house was 1647 square feet. This means each square is 16.47 square feet or approximately 4'x4'. The Save-interface in The Sims is poor.