Biology is the scientific study of life, encompassing topics like cells, genetic information, evolution, energy processing, and ecosystems. All living organisms are made up of cells and share genetic information. Evolution explains life's unity and diversity. Energy processing drives movement, growth, and reproduction, while organisms maintain internal balance. Biologists use the scientific method to explore life from cells to ecosystems. Life on Earth began over 3.7 billion years ago, resulting in diverse organisms that contribute to ecosystem balance.Ancient Egypt and Mesopotamia (3000-1200 BCE) laid the groundwork for science and medicine, influencing Greek natural philosophy. Greek philosophers like Aristotle (384-322 BCE) expanded biological understanding by exploring causation and diversity. Islamic scholars like al-Jahiz, Al-Dīnawarī, and Rhazes contributed to botany, anatomy, and medicine, drawing from Greek traditions.Advances continued with Anton van Leeuwenhoek's microscope improvements, revealing microscopic life. Jan Swammerdam's work in the 17th century advanced entomology. In the 19th century, cell theory gained prominence through Schleiden, Schwann, Remak, and Virchow.In the 18th century, Carl Linnaeus developed taxonomy, while Buffon hinted at common descent. In the mid-19th century, Charles Darwin and Alfred Russel Wallace independently proposed natural selection. Gregor Mendel initiated genetics, integrated with evolution in the modern synthesis. DNA's role as genetic material was confirmed by Hershey, Chase, Watson, and Crick. Molecular genetics flourished in the mid-20th century, culminating in the decoding of the genetic code and the Human Genome Project's launch in 1990.