Like any other operating system, Ubuntu comes with the ability to connect to the internet via a wireless network. However, some wireless network cards require the installation of a proprietary driver in order to work properly. If this is the case for you, you can find and install the necessary driver you need through Ubuntu's Software and Updates. This tutorial will walk you through all of the steps in establishing your Ubuntu wireless connection. Click the roundel button in the upper-right corner of your Ubuntu desktop, and select System Settings > Software and Updates. Then, go to the Additional Drivers tab, and check to see if any proprietary drivers need to be downloaded for your wireless network card.
If a driver is necessary, you will need to connect your computer to the internet cable network to perform the download. If no download is necessary, you can begin setting up your WiFi connection.
Click the WiFi icon located at the top-right of your desktop to see a list of the available WiFi networks. If your network does not appear, click Connect to a hidden wireless network. Select your network, and enter the password to establish a connection.