Nitrogen fertilizers are substances that provide essential nitrogen to plants, promoting healthy growth and increasing crop yields. They are commonly used in agriculture to enhance soil fertility, as nitrogen is a vital nutrient that supports processes like photosynthesis and protein synthesis. These fertilizers come in various forms, including urea, ammonium nitrate, and calcium nitrate. Each type has different properties and application methods, allowing farmers to choose the best option for their specific soil and crop needs. Proper use of nitrogen fertilizers can lead to improved plant health and productivity.