Take a look at the periodic table below. The periodic table contains information about each element known to scientists, starting with the name and the chemical symbol. Each vertical column of the periodic table is called a group; each group of elements is like a family of elements. The elements in a group all have similar properties. Each horizontal line contains elements that are also related. These are called periods, and you will learn more about them later.

The periodic table also contains information on the atomic number of each element. In this lesson you will learn more about what the atomic number means and how the arrangement of elements into groups and periods can give you information about each element. Without the periodic table, it would be difficult for chemists to remember the properties of all the elements. The periodic table organizes the elements by their properties.