Some times we install programs by mistake. Especially when young children use the computer, they go on clicking. In the process sometimes we get unwanted programs on our computer. They can be viruses or just enough to slow down your computer. It is important to uninstall these programs. To uninstall go to Settings, Apps. Go through the Apps one by one. Look for the ones that looks suspicious that you did not install. Uninstall them. It is good to do this whenever you feel your computer is slowing down.