The periodic table is organized by increasing atomic number (the number of protons in an atom's nucleus) from left to right and top to bottom. It is arranged in horizontal rows called periods and vertical columns called groups. Elements in the same group have similar chemical properties due to having the same number of valence electrons. The table is also divided into blocks based on electron orbital types (s, p, d, f blocks). Metals are generally on the left and center, non-metals on the right, with a zig-zag line dividing them. The table allows prediction of element properties and shows periodic trends as atomic number increases.
