Input.GetAxis

Description

Returns the value of the virtual axis identified by axisName.

The value will be in the range -1...1 for keyboard and joystick input. If the axis is setup to be delta mouse movement, the mouse delta is multiplied by the axis sensitivity and the range is not -1...1.

This is frame-rate independent; you do not need to be concerned about varying frame-rates when using this value.

To set up your input or view the options for axisName, go to Edit > Project Settings > Input. This brings up the Input Manager. Expand Axis to see the list of your current inputs. You can use one of these as the axisName. To rename the input or change the positive button etc., expand one of the options, and change the name in the Name field or Positive Button field. Also, change the Type to Joystick Axis. To add a new input, add 1 to the number in the Size field.

using UnityEngine;
using System.Collections;

// A very simplistic car driving on the x-z plane.

public class ExampleClass : MonoBehaviour
{
    public float speed = 10.0f;
    public float rotationSpeed = 100.0f;

    void Update()
    {
        // Get the horizontal and vertical axis.
        // By default they are mapped to the arrow keys.
        // The value is in the range -1 to 1
        float translation = Input.GetAxis("Vertical") * speed;
        float rotation = Input.GetAxis("Horizontal") * rotationSpeed;

        // Make it move 10 meters per second instead of 10 meters per frame...
        translation *= Time.deltaTime;
        rotation *= Time.deltaTime;

        // Move translation along the object's z-axis
        transform.Translate(0, 0, translation);

        // Rotate around our y-axis
        transform.Rotate(0, rotation, 0);
    }
}

using UnityEngine;
using System.Collections;

// Performs a mouse look.

public class ExampleClass : MonoBehaviour
{
    float horizontalSpeed = 2.0f;
    float verticalSpeed = 2.0f;

    void Update()
    {
        // Get the mouse delta. This is not in the range -1...1
        float h = horizontalSpeed * Input.GetAxis("Mouse X");
        float v = verticalSpeed * Input.GetAxis("Mouse Y");

        transform.Rotate(v, h, 0);
    }
}

Note: The Horizontal and Vertical ranges change from 0 to +1 or -1 with increase/decrease in 0.05f steps. GetAxisRaw has changes from 0 to 1 or -1 immediately, so with no steps.