Input devices for portable computers come in different forms. Most of the input devices come built-in or provided separately by the manufacturer. You also have bunch of third-party input devices that you can use according to your preference and needs.
Laptop keyboards are quite different than desktop keyboards. This is because the keys are generally crammed into smaller form factor. They do use the QWERTY format. Manufacturers choose the size of the key and placement of the non-alphabet characters.
Every, almost, keyboard out there uses a key called Function (fn). With the help of this function key you are able to perform some extra functions for keys. You either hold the key to access traditional function or combine the function key with other to perform some specific functions. This could be, controlling media player to opening up browser, Windows file explorer etc. You have the privilege to modify this behaviour on some systems.
Portable devices need mouse interaction as well and they need some way of controlling this behaviour. Other than any built-in solution provided by the manufacturers. These portables have extra USB ports and this port can be used to plug into any kind pointing devices you see and find on desktop.
Early portables had trackballs, often plugged in like a mouse and clipped to the side of the device. Other models with trackballs placed them right in front of the keyboard at the edge of the case, closer to the user or behind the keyboard, somewhere at the edge of the screen.
Next came in IBM’s TrackPoint device. This was a joystick with the size of a pencil eraser, placed at the centre of the keyboard. With this TrackPoint you were able to move the cursor around without having to be away from the home hand positioning. You had to slightly push the joystick to navigate around and click/ right click using the button resided right beneath the space bar. This spread the word and since then was adopted by other manufacturers as well, of course licensed. This TrackPoint still found in laptop keyboard now. For instance you will find this on Lenovo ThinkPad.
The most widely found pointing device now is the touchpad. This is a flat, touch sensitive pad, typically, right beneath the keyboard. This is super easy and by now I am sure you know how this works. In case, you simply touch the pad and navigate the cursor around the screen and select/ click/ right-click with buttons on the bottom or on the surface. This is not a big deal and requires just getting used to the touchpad. The biggest upside of this is, there is no moving part here and extremely durable in terms of longevity over previous generation technologies. You can simply adjust the sensitivity and make other changes by going to the Settings, then to devices and to Mouse dialog or Mouse applet in control panel.
Lot of manufacturers now include multiTouch touchpad, which allows you to do things using your other fingers at the same time. For instance, scrolling while navigating, swiping to another screen or desktop etc. Multi-touch trackpad was pioneered by the Apple’s laptops and removed the lack of mouse experience from the new laptops.