Simple Jump script

I need a simple jump script for a 2d game.

 #pragma strict
 var mySpeed = 100;
 function Start () {
 InvokeRepeating("Multiplier", 0, .1);
 }
 
 function Update () {
 
     
     
      GetComponent.<Rigidbody2D>().velocity = Vector2(mySpeed,0);
      
      if (Input.GetButtonDown ("Space"))
      {
         //Jump script should go here
      }
      
      
      }
      
 function Multiplier ()
 {
     mySpeed++;
 }

I am relatively new to unity so please give me any suggestions in changing my scripts.