Well, I'm going to assume you want Google Chrome, which is the only way to get Adobe Flash 15 on Ubuntu. First, open up a terminal and type uname -p. That will tell you your processor architecture. If you already know it, skip this. If it says x86_64, you have a 64-bit processor (remember that for later). If you get iX86, where X can be 3, 4, 5, or 6, you have a 32-bit processor (remember that). If you get x86, that also means you have a 32-bit processor (it goes without saying, but remember that). Then use any old web browser like Mozilla Firefox or Midori to go to and click the big blue "Download now" button. You'll see a box pop up asking you to choose from four different versions of Chrome. You want one of the top two (the .deb files) depending on if you're 32 or 64 bit. Click the appropriate radio button, scroll down, read the license agreement (like anybody ever does) and choose "Accept and Install". In some browsers, including Mozilla Firefox, you will be asked whether you would like to open or save the file. Choose "Save" or something similar depending on your browser. Let it download. Once it has completed downloading, open your file browser (Nautilus a.k.a. Files, Dolphin, Thunar, etc.) and go to your Downloads folder or where ever the file was downloaded to. Right-click on the file, move down in the menu to "Open With..." and choose "Ubuntu Software Center", "Muon", or "GDebi", whichever appears. Click "Install" and follow the instructions to install the file. Once it has been installed, you have successfully downloaded Google Chrome and Adobe Flash Player, but Adobe Flash Player will only work in Google Chrome. Now that's taken care of, let's move on to Java.