Irrigation is, in simplest terms, the practice of artificially applying water to crops and plants, and hence is an agricultural practice. Irrigation is required to provide sustained water to crops. Historically, human beings were dependent on rainfall for satisfying crop's needs of water. However, since most of the areas experience rainfall only for a fraction of year, we looked for alternate means. Artificial water supply is carried out by using water from rivers (or lakes and ponds), groundwater sources (using pumps), etc. Depending on how the water is applied to crops, irrigation has different types, including drip irrigation and sprinkler-based irrigation, etc. Irrigation has ensured consistent water supply to large parts of fertile lands in countries like India and this has resulted in increased food production and saved millions from hunger and famine.
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