Tissues are groups of similar cells that work together to perform a specific function in the body. There are four main types of tissues: epithelial, connective, muscle, and nervous. Each type has a unique role, such as protecting organs, supporting structures, enabling movement, or transmitting signals. In our bodies, tissues combine to form organs, like the heart or lungs. For example, the heart is made up of muscle tissue that helps it pump blood, connective tissue that supports its structure, and nervous tissue that controls its rhythm. Understanding tissues is essential for studying how our bodies function.