Does this need charging?

In this time of smartphones, tablets and ereaders, one device or another may be low on electricity or altogether out of juice.  I have read in several places that many devices that rely on a re-chargeable battery can serve longer if they are charged only to 60 or 80% of their capacity.  I am still aware that my laptop computer is considerably more powerful than my other devices.  But despite being relatively lightweight and portable, my connected devices have more limited choices on each page than the computer.  I have more choices on web pages, choices that I make use of with the computer.  Besides, I keep the computer connected to electricity continuously.  I don't have to check the computer's power level.  It never needs charging.