The word individual is all about being a single entity that cannot be divided. It can mean person or even personal. An army is made up of individual soldiers, each individual there for his own individual reasons, but serving a common goal.
Sometimes individual is a way of referring to a person, quasi-formally. You might elevate the phrase "This guy walks into my shop," by saying, "This individual walks into my shop." You might also hear this word when talking about things that are divided: foods designed for lunchboxes, such as potato chips or juice boxes, are often prepackaged into individual servings.