The purpose of this page is to teach one how to type a literal sigma character using a keyboard.

• Remember, you can always copy and paste a sigma like you would with any other string. I still do not mind being called Sigma.
• Σ, Σ, or Σ can be used to display a sigma. These entities can also be used in the search box.

If you are reading this on a Windozer, you may be able to use an alt code to type non-Latin symbols. Using the numberpad, hit Alt+228 and release.

That may have produced a different character. If so, your system has been configured to use code page that is not 437, probably for a different language or region.

You can change the code page by changing the 'format' option (the dropdown box) under the 'Formats' tab at 'Control Panel' -> 'Region and Language'. There are alternatives to changing the code page, though.

It may be worth noting that this is only the configuration I use. Other input methods may support `u.

This works on Windows 7.

1. Go to 'Control Panel' -> 'Region and Language'.
2. On the 'Keyboards and Languages' tab, press the 'Change Keyboards' button.
3. A new window should have appeared. Press the 'Add' button.
4. You should now see a list of languages with their countries. Under 'Chinese (Traditional, Taiwan)' check the box labeled 'Chinese (Traditional) - New Phonetic', and then OK.
5. Select the field that says 'Chinese (Traditional, Taiwan)', and then press 'Properties'.
6. Under the 'Advanced' tab, there should be a table mapping property names to your setting. Change the 'Leading key' field to the backtick (`) and then OK.
7. Now, in the window that was opened in step 2, go to the 'Advanced Key Settings' tab. Change the key sequence for 'Chinese (Traditional) IME - Ime/NonIme Toggle' to Ctrl+Space.
8. Save the changes. Logout and back in if nothing happened.
9. Open your favourite text editor, hit Ctrl+Space, and type `u03a3, a space, and then hit ↵ Enter. A sigma should have appeared at the caret position.
10. You can switch out of this input method by hitting Ctrl+Space again.

There are two common methods for direct input of Unicode characters. These methods will not work with SCIM installed.

• Hold Ctrl+⇧ Shift and type u followed by 03a3. Then release Ctrl + Shift.
• Enter Ctrl+⇧ Shift+u, then type 03a3, and press ↵ Enter or Space.

Installing SCIM will remove the capability described above. There is a package, scim-rawcode, that imitates that feature. You can set Ctrl+⇧ Shift+u to be the shortcut for switching to the rawcode input method. After switching to rawcode, you can type 03a3, and press ↵ Enter or Space.

Certain Linux machines have Greek compose files preinstalled. If Greek compose files are installed, you can press Compose+G+S one at a time to type out the sigma. If you do not have a Greek compose file, get one here.

Hold Ctrl+⌘ Cmd+Space and type u+03a3. You can then either select the character with the mouse or press ↓ and hit ↵ Enter.

Typing ⌥ Option+W will produce ∑, which is the Unicode summation symbol. This looks similar to Σ, but is a distinct character.