A dual-core processor is sufficient for a laptop. The primary function of the cores is that they provide the computer to do multitasking. So, you can run several applications at the same time. You can listen to your favorite music during browsing the internet and working on your MS Office files simultaneously. But a quad-core computer is better if you are a heavy user. If you are doing jobs like photo editing, music production, or working on other complicated engineering software, you have to choose a multi-core laptop.