OS X Yosemite: Use input sources to type in other languages
To type in a different language without having a keyboard designed for that language, add an input source for the language, then switch to it when you want to use it. You can type in any language that uses the same script or alphabet as the current input source.
Add input sources
Choose Apple menu > System Preferences, click Keyboard, then click Input Sources.
Click Add , search for a language or input source, then select one or more input sources.
When you add an input source, the option to show the Input menu in the menu bar is automatically selected. The Input menu lets you quickly switch input sources as needed.
Switch between input sources
Choose an input source from the Input menu in the menu bar. If an input source is dimmed, the current app doesn’t support it.
You can also press Option-Command-Space bar to select the next input source in the menu, or Command-Space bar to select the previous input source. If Spotlight opens instead, you need to change the conflicting keyboard shortcuts. For more information, see If Spotlight opens when you switch input sources.
When you add input sources, those languages are automatically added to the list of preferred languages in Language & Region preferences; you can set your Mac to use one of those languages.
When you choose an input source that doesn’t match your keyboard, the keys you see and press on your keyboard may be different from the characters that are displayed when you type. To see which keys to press, use the Keyboard Viewer.