jest express testing

Step 1: Install Jest using npm or yarn. Step 2: Write test files with .test.js extension to define test cases. Step 3: Use the describe() function to group test cases. Step 4: Use the test() function to define individual test cases. Step 5: Use expect() and matchers (e.g., toBe(), toEqual()) to make assertions. Step 6: Run tests using the jest command or npm test.