There are seven elements on the periodic table that have some characteristics of metals and some of nonmetals. These elements are called metalloids. The most common metalloid is silicon. A picture of a chunk of silicon is shown below.

Source: Silicon, chemicool

Where have you heard the term silicon before? Perhaps you have heard of a silicon computer chip.

The most useful property of metalloids is their varying ability to conduct electricity. Whether or not a metalloid conducts electricity can depend on the temperature or the exposure to light. For this reason metalloids, such as silicon or germanium, are used to make semiconductors. Semiconductors are substances that under some conditions can conduct electricity, behaving like a metal. In other conditions, semiconductors cannot conduct electricity, behaving like a nonmetal. Semiconductors are used to make computer chips, transistors, and lasers.

Watch this video to learn more about the metalloids and their properties and uses.