Soil types are classified based on their texture, composition, and drainage properties. The main types include sand, silt, clay, and loam. Sand has large particles, allowing for good drainage but low nutrient retention. Silt has smaller particles, retaining moisture and nutrients better than sand. Clay has the smallest particles, which can hold water but may drain poorly. Loam is a balanced mixture of sand, silt, and clay, making it ideal for gardening and agriculture due to its fertility and good drainage. Each soil type supports different plant growth and affects water retention, making it essential for ecosystems and farming.