Unity users can easily monitor CPU and Memory usage by using indicator-sysmonitor application.
To install it, you just need to add alexeftimie PPA repository using these simple command:
sudo add-apt-repository ppa:alexeftimie/ppa
sudo apt-get update
sudo apt-get install indicator-sysmonitor
Note that this doesn't work on previous Ubuntu 10.xx releases.
Alternatively, you can install Conky by running the command:
sudo apt-get install conky
There were innovative advances in the operating system introduced to the market involving multi user and multi processing aspects. And there was the need of purchasing an additional cooling component to keep the operating system stable, leading to a higher price. Otherwise, the computer temperature will be very high.