The main idea of pretty much any chess opening is to develop pieces as quickly and effectively as possible. Here are some basic principles for white which can be applied for most opening situations in the world:

• Try to form a solid pawn center. By solid pawn center I mean c, d and e pawns or d and e pawns. It's very good to place these pawns on the 4th rank. The "ideal" structure for white could look something like this: Pawns: d4, e4 - to influence central squares c5, d5, e5 and f5.

Knights: Nc3, Nf3 - to double attack the center, to safeguard the king (e-2 square).

Bishops: Bc4, Bf4 - to take a control of a2-g8, a6-h1, c1-h6 and h2-c7 diagonals.

King: Kg1 (after "O-O" castle king side) - to ensure safety of a king.

Rooks: Rd1, Re1 - to take a control of semi open files.

• The knights are strongest in the center and weakest at the corner because they are short distance pieces (can only attack in close range). Therefore, knights should be developed on c3 and f3 squares where they are powerful, closer to the center.
• Bishops, in contrast with knights, are long distance pieces. Therefore, it is crucial for bishops take control of diagonals, especially of long diagonals (a-h diagonal).
• Rooks should be placed on open files or on places where a file will open up.
• Queen is a universal piece since it can control both ranks/files and diagonals. However, it's not a very good idea of develop a queen fast since it can easily become a target of enemy forces.