Set the traps! We have an infestation!

Of course, I don't mean an actual living mouse (or mice, as the case may be). I am, of course, instead referring to the pointing device that connects to a person's computer. Over the years, I've gotten very familiar with the personal computer, and I have seen several different types of these buggers over the years, especially while working in the field of recycling electronic waste. Probably the biggest improvement we've made this century is eliminating the need for that stupid ball that every high school kid (except me) has stolen at least once, and replacing it with an optical sensor that is almost akin to a robotic eye, as seen below.

Mechanical v. Optical mice, as shown in this diagram.

Most of these come in the form of two or three buttons. Others, especially those made by Apple, usually only have one gigantic button, or a sensor that can mirror either one button or two. In recent years, although probably as far back as Windows 98, manufacturers started replacing the middle button with a scroll wheel instead of the full middle button. This made browsing web pages easier, as well as file folders and other programs where all of the information presented to the user could not fit on the screen at one time. Somewhere along the line as well, some internet user(s) that designed mice for a living also decided that they were too lazy to click the browser buttons on their computers, and so we also started seeing "browser buttons" on mice as well, such as the IBM Optical Navigator Mouse (not actually manufactured by IBM, but whatever).

Logitech trackball with scroll wheel. 

Before the rise of the optical mouse, however, we saw the rise of the trackball. Apple was probably the only manufacturer to actually include it on a laptop, but don't quote me on that. With practice, proper care, as well as proper usage, they can prove themselves to be quite useful, especially for the trade of computer graphic design. I remember using one a lot throughout my childhood because my father preferred them to traditional mice. In that respect, they are still easier to clean than a mouse, but still not practical unless you're the exact niche audience for using one. Personally, I still say get me an optical mouse any day over this.

An example of a touch pad, as outlined above. 

And then there's this thing. Originally a laptop exclusive, Apple has tried making them mainstream in their desktop market, although the success rate, as far as I'm concerned, is unknown, because I am not an Apple enthusiast. In recent years, manufacturers have tinkered around with how to "improve" them, such as streamlining the buttons, which makes the scrolling surface bigger, to adopting previous niche features, such as Apple's two-finger click  for right-clicking. Personally, I still prefer a mouse, but if I had to use a touch pad, I'd prefer one with two physical buttons and a smaller scrolling area. Sure, that might make me a simpleton, but if it isn't broke, don't go looking for a fix to it "just because."