mongodb what is aggregation used for code example

Example 1: MONGODB AGGREGATION tutorials

db.stocks.aggregate([
  { $match: { "price": 2000 } }
])

Example 2: MONGODB AGGREGATION tutorials

db.stocks.insertMany([
   { name: "Infosys", qty: 100, price: 800 },
   { name: "TCS", qty: 100, price: 2000 },
   { name: "Wipro", qty: 2500, price: 300 }
])