The 100+ existing elements  are organized into a table known as the Periodic Table. The familiar looking shape of the table is based upon a number of observations about the elements. One of those observations was that there were groupings of elements that had very similar properties. These elements were placed in the same column, referred to as families, and given family names such as alkali metals, alkaline earth metals, halogens, and noble gases.
 

Much of what you need to know to answer this question is discussed in the Fundamentals section above. But if you would like to further your understanding, inspect and study the infographic below on the topic.