Is there a way to quick type spanish accented letters? What about the upside down question mark? Having to click the letters can get tedious and annoying...
If you are using Windows, install "United States-International" keyboard.
You can install it manually or click on the "Fix it for me" link to download a software and it will install "US-International" keyboard for you.
The below link shows you the keyboard shortcuts to type: ñ áéíóú ¿¡
I installed the Spanish (Mexico) keyboard. It works great, although if you have a standard English keyboard you have to practice at remembering where all the proper keys are. I considered getting a second keyboard and buying Spanish keyboard stickers from eBay (stickers are less then $5) Switching between different keyboards is easy. The standard hotkey combo is alt-shift on the left of the keyboard.
I found this site very useful also when I forgot where things were on my English keyboard http://www.spanishdict.com/answers/100808/how-to-type-spanish-letters-
If you have a Mac you can press option + e for accents and option+n for tildes
I think the strength of Linux is customization, however it is also its weakness. Different distributions or different desktops may have different ways to set and use your keyboard. So, there is no universal sure way to do it. If you are using Ubuntu, these following websites would help you with that.
If you are using the Unity interface, on the side menu bar (launcher), click the "Dash Home" (the Ubuntu logo at the top). Type "keyboard layout" and click on it. You will see a list of keyboard layouts that you have already installed (for example: English). Click on the "+" sign at the bottom of the list. Then select "English (international AltGr dead keys)". Close everything , you are done. Select the "English (international AltGr dead keys)" keyboard from the "Application Indicator (the top bar where the envelope is)". Now you can use the right ALT key type accents. To get é : while holding the ALT , press quote key; release all keys, then press e.