Biomarkers are measurable indicators that help scientists and doctors understand biological processes in the body. They can be substances like proteins, genes, or hormones that signal the presence of a disease or the effectiveness of a treatment. For example, a specific protein in the blood might indicate the early stages of cancer, allowing for timely intervention. These markers are crucial in personalized medicine, where treatments are tailored to individual patients based on their unique biomarker profiles. By analyzing these indicators, healthcare providers can make more informed decisions, improving outcomes for conditions like diabetes or heart disease.