Indicator strips are small pieces of paper or plastic that change color when exposed to certain conditions, such as pH levels or temperature. They are commonly used in laboratories, swimming pools, and aquariums to provide a quick visual indication of chemical properties. These strips often contain special dyes that react to specific substances. For example, pH indicator strips can show whether a solution is acidic or basic by changing color. This makes them a useful tool for both professionals and hobbyists who need to monitor and maintain proper chemical balances in various environments.