Okay kiddo, irrigation in Vietnam is when people use water to help grow their crops. Vietnam is a country that gets a lot of rain, but sometimes the rain doesn't come when the plants need it. So, farmers use different methods to get water to their plants.
One way they do this is by digging small channels in the ground so water can flow from a nearby river or lake to the crops. This is called surface irrigation. Another way is by using a well to pump water up from underground and then letting it flow through small channels to the fields. This is called groundwater irrigation.
Sometimes, farmers also use sprinklers and hoses to spray water directly on the plants. This is called overhead irrigation. This way, they can control exactly how much water the plants get and when they get it.
Irrigation is really important in Vietnam because it helps farmers grow more crops and feed more people. It's also important for the economy because Vietnam exports a lot of food to other countries.
But, some people say that using too much water for irrigation can harm the environment by depleting water resources or causing soil salinization. So, it's important to use irrigation methods that are sustainable and don't harm the environment in the long run.