A few months back I bought a new MacBook Air. I absolutely love it, it's the best computer I've ever owned. I'm pretty sure I say that about every new computer I get, but this one is head and shoulders above the rest.
Upgrades in the past used to be just incremental updates to the processor, memory, and hard drive. This machine has all of that, but what's amazing is how much faster it feels than every other upgrade I've done. It's really no surprise when you think about it.
There are really only 2 main driving forces that relate to the performance of any application: its use of the procesor, and its use of the hard drive1. Yes, I'm simplifying here, but typically when you want to optimze a program you need to look at those 2 things.
When a program uses a lot of processor cycles its said to be CPU-bound. That is, the program's performance is bound by the speed of the processor. Conversely, when a program reads and writes to the hard drive a lot it's said to be I/O bound; the performance of the program is bound by how quickly it can read and write data. Very rarely will you ever see a program that's solely CPU bound or I/O bound. Usually different parts of every program have different performance characteristics.
So why is it no surprise that the MacBook Air feels so much faster than any other computer I've ever owned? The MacBook Air has a solid state drive. Solid state drives are a new class of storage media. They optimize for speed while sacrificing total size. To give you an example, you can buy a 256GB SSD for roughly the same price as a 4TB spinning rust2 drive. But the speed of these drives is amazing due to how they work. SSDs have more-or-less direct access to any piece of information on the drive. Traditional hard drives have to wait for a spinning platter to come within range of a little arm that can picks the data off the drive. There are physics involved here, traditional hard drives will never be as fast as an SSD, but if you need a lot of storage space you can't go wrong.
You can get an SSD for pretty much any computer, but at this point they're a fairly expensive upgrade. It's been said before that installing an SSD is just like getting a new computer. And while my MacBook Air is certainly a new computer, it feels amazing every time I use it. It's fast. Faster than anything I've ever used before, and that's mostly thanks to the SSD.
There's a lot more that can be said about the MacBook Air. It's simple, tossing out things that most people rarely need anymore like DVD drives, FireWire, and extra USB ports. It's ultra lightweight, something that's really nice to have regardless of whether you care about the weight or not. The choices you have to make are pretty minimal; pick a screen size, processor and memory. The price is very reasonable for a premium product. The fit and finish is excellent. All told, the MacBook Air truly is the Volkscomputer.
- Yes, I'm simplifying quite a bit here. Performance can also be affected by how much parallel computation a program can do, the layout of the program in memory so that it makes efficient use of the CPU's caches, etc.
- The term spinning rust refers to the fact that traditional mechanical hard drives contain rust colored platters that spin. Wikipedia has a great article about how these types of drives work.
