Summary
Highlights
Just as 26 letters form all English writings, almost everything in nature, from microbes to mountains and stars, is made from a few building blocks, about a hundred of them. These building blocks are called elements.
Elements are pure substances that make up almost all matter around us. For example, water is made of hydrogen and oxygen. Living beings are primarily composed of oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus. Rocks are mostly made of silicon, oxygen, aluminum, magnesium, and iron. To understand matter, we must study these elements.
Elements are arranged in the periodic table, where each element has a square, a number, and a symbol (an abbreviation). Some symbols use the first letter of the element's English name (e.g., H for hydrogen, C for carbon). To distinguish between elements with the same first letter, the first two letters are used, with the first letter capitalized and the second lowercase (e.g., He for helium, Ca for calcium).
Some element symbols originate from older names in different languages. For instance, 'Na' for sodium comes from 'natrium' (Latin), 'Au' for gold from 'aurum' (Latin), 'Pb' for lead from 'plumbum' (Latin), and 'W' for tungsten from 'wolfram' (German).
In summary, almost everything in the universe is made of about a hundred elements, also known as pure substances, arranged in the periodic table. Understanding how these elements combine is key to understanding matter, similar to how different LEGO pieces can be combined to build countless structures.