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Operating system projects have been made by many Scratchers. Scratch does not have the capability to create a true operating system. However, it is possible to create a simulation of one. (Note: This article will take a long time to create.)

Making Sprites

Begin by creating the sprites for the Operating System, as shown below.

List of OS Sprites.png

  • Loading sprite
  • Logo
  • Password Manager
  • Games, apps, etc.

One can also add other sprites for example a menu sprite or a user profile picture sprite.


Fading in can be used as a transition. This is a way of making a fade in effect using the ghost effect block:

when gf clicked
set [ghost v] effect to (100)
repeat (25)
    change [ghost v] effect by (-4)

Fading out can also be used as an ending effect. This is a script for a fade-out effect:

when gf clicked
set [ghost v] effect to (0)
repeat (25)
    change [ghost v] effect by (4)

These transitions use one of the Graphic Effect blocks called the Ghost Effect.

To create certain movements, some operating systems use physics. To do this, first, create a variable called x velocity or something similar. This variable will calculate the x velocity.

Now, write the following script:

when gf clicked
set [x velocity v] to [5]
repeat (50)
    change x by (x velocity)
    change [x velocity v] by [-0.1]

As the velocity reduces, the speed of the object reduces. So, eventually, the object will come to a smooth halt. Every time the function is called, the velocity will reduce by 0.1. The user can then edit the script to their needs.

You can also do this with sizes. To make an object bigger when your mouse is hovering over it, you can write this script:

when gf clicked // you can also use a broadcast
if <touching (mouse-pointer v)?> then
change size by (((size)-(125)) / (6)
change size by (((size)-(100)) / (6)

This uses size blocks to slowly make the sprite bigger when your mouse-pointer is over it, and smaller when it's not.


Some operating systems contain loading screens. To make a loading screen, first, create a sprite with different costumes for loading. Then, one could use this script to make a loading screen:

when I receive [load v]
repeat (pick random (1) to (20))
    wait (0.3) secs
    next costume
broadcast (password v)

Another idea is to create a logo for the project. Try to make a logo that represents the project. When the logo is made, this script will make it show/hide at the appropriate time. One also may want to use the smooth transitions and fade in/out effect for this.

when gf clicked

when I receive [password v]

User Management

One can add a password to an OS. To make one, create a variable called (password). Then, place these scripts:

when gf clicked
set [password v] to [] // insert any text

After setting the password, place these scripts:

when I receive [password v]
ask [Password please] and wait
if <(answer) = (password)> then // If the password is correct, it loads
say [Loading…] for (pick random (1) to (8)) secs
broadcast (OS Complete v)
say [Sorry, please try again.] for (2) secs
broadcast (password v) // this will re-run this script
when I receive [OS Complete v]
... // these scripts will run if the password is correct

Or, this workaround can be used:

repeat until <(answer) = (password)>
ask [Password please] and wait
say [Loading...] for (pick random (1) to (8)) secs
broadcast (OS Complete v)

What the script does is it asks the user to enter the password the user set. If it is correct, it will go to the loading screen and load the operating system. But if the password is wrong, it will say the user will have to log in again.

Note Caution: These passwords are not private. A user can see the passwords by clicking the "See Inside" button on the project page. It is recommended to not store personal information in the OS and to have a default password/passcode.
Note Note: Remember to leave the manager sprite blank.


Applications or programs are the main part of an OS. They can range from pong games to music to chat bots. Being unique in their applications will help make their OS stick out. A good suggestion would be to add mini games, sounds, and more.

When all of the apps are created, replace all when gf clicked with when I receive [message1 v]. This can reduce lag. Make sure that the script

when gf clicked
broadcast (message1 v)

is somewhere in your project.

Note Note: The script above should be within the apps.

Official Operating Systems

This tutorial explains how to create a Scratch project with the stereotypical user interface of an operating system, but the project does not actually simulate or emulate an operating system. Real operating systems are more complicated and involve many different parts, such as the boot loader and kernel, and may not necessarily support a GUI. The most common operating systems include Windows, Mac OS, Linux, Chrome OS, FreeBSD, Android, or a platform-specific version of iOS.

See Also

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