Most modern laptops come with a built-in external display output that allows you to connect an additional display to the laptop. The laptops also allow you to configure the external display with a resolution and color depth different from the laptop screen. You can add additional displays to a laptop by using USB display adapters:

Adding more displays using multiple USB display adapters

Using a USB display adapters, you can add more displays to your laptop. A USB display adapter connects to the USB slot in your laptop on one end and allows you to connect a display at the other end. This option is more convenient than the multi-monitor graphics card option as it does not require you to open the laptop for changing the display card. Note that USB-to-VGA display adapters suffer from speed limitations of the current USB 2.0 interface. This makes the USB-to-VGA option suitable for less demanding applications.

A single USB display adapter supports one VGA, DVI or HDMI output. For connecting 2 more displays to your laptop, you need a couple of these USB-to-VGA adapters.

Click here to see a list of available USB display adapters from Amazon.