app.send is not a function

 Error:- 

TypeError: app.send is not a function

    Error code:- 

const express = require('express')

const app = express()

const port  = 8080

app.get("/",(req,res)=>{

    app.send("This is my first app");

})

app.listen(port,()=>{

    console.log(`The server is run on the port no ${port}`)

})

Solution code :- 

const express = require('express')

const app = express()

const port  = 8080

// ye wali get method hai

app.get("/",(req,res)=>{

    res.send("This is my first app");

})

app.get("/about",(req,res)=>{

    res.send("This is my first app about page");

})

// niche wlai post method hai

app.post("/about",(req,res)=>{

    res.send("This is my first app about page");

})

app.get("/about",(req,res)=>{

    // apko agar status code send karna hai to aap aise bhej sakte hai

    res.status(200).send("This is my first app about page");

})

app.listen(port,()=>{

    console.log(`The server is run on the port no ${port}`)

})