When looking at computers (either a desktop or laptop) you might sometimes hear the term "bottle neck" being used. More often then not when you hear general consumers talking about it in terms of computers they referring to limitations in general computer hardware that causes a particular machine to not go as fast as it could potentially go. Of course none noobs can obviously just ignore this. But for all others when looking to buy a new system this might be something you want to consider if for some reason you need your computer to run very-very  fast, say for digital video editing, high end audio editing, dedicated video gaming or even industry CAD applications???!

But for most general users it wouldn't be too much of a concern. There's only so much power and speed you actually need just  for sending email, IM messaging, browsing the internet, typing up word notes or just generally putting together office documents. However lower level access remote desktop viewing/monitoring and discrete cloud server resource access or mirroring via JVM's over a broadband connection can more often then not put quite a strain on what should be more then ample hardware resources to handle general day to day internet related tasks. If you find that your machine is constantly hanging and locking up whilst connected to the internet try completely disconnecting it and you should notice it suddenly become very-very fast again.  Although that's a bit pointless really if you actually need to use your computer to do things on the internet with. 

Obviously the speed of a computer is measured in frequency of clock cycles per second. Most computers nowadays will have a clock cycle rating in Gigahertz (GHz),  the "Giga" part meaning number groupings/units of a thousand. So 1Ghz is 1000 Megahertz (MHz). When I first started out my first tower desktop was 33MHz. (or 66MHz in turbo mode) with 4MB of ram (maybe 12MHz?) and a 200MB hard drive. That was like, ... (thinking)...  maybe around the start of the 90's. 

Generally I was thinking laptops here. Mainly because they've become a lot more powerful whilst being able to consume significantly less electrical power to do many of the same things that you might go about doing on a full blown desktop.

Simple hardware examples

- 2.4GHz core 2 duo processor with 677 FSB
- Maximum system bus transport speed 677 FSB
- 2GB DDR2 677MHz RAM

The above example could be said to not really have a bottle within the bounds of its maximum threshold when looking at just these three things. A couple of ways to speed the above example system up through basic hardware upgrades is to install 4GB of DDR2 677MHz RAM (if it can accommodate it) or use a suitable SSD instead of regular HHD although obviously SSD's are still very expensive compared to regular HHD's with significantly less storage space also when looking at it in terms of its value per megabyte. No doubt doing both of these things rather then either or would make it even faster.There'd be no point installing ddr2 800MHz ram since it would still be stuck at 677MHz due the limitation of the system bus transport speed and CPU FSB.

- 2.4Ghz core 2 duo  processor with 800MHz FSB
- Maximum system bus transport speed 800MHz FSB
- 4GB DDR2 677Mhz RAM

The bottle neck here within the bounds of these three things would obviously be the RAM in terms of its speed.  You could use 4GB of DDR2 800MHz RAM instead if it mattered that much. There's also the option to use an SSD instead of a HHD to boost speed even further.

- 2.4Ghz core 2 duo processor with 1066MHz FSB
- Maximum system bus transport speed 800MHz
- 4GB DDR2 677MHz RAM

Here its obviously the RAM and the system FSB against the CPU's maximum FSB rating.

- 2.4GHz core 2 duo processor with 1066MHZ FSB
- Maximum system bus transport speed 1066MHz FSB
- 4GB DDR3 1066MHz RAM

A matched system across the parts we're looking at here in terms of the maximum threshold.

- 2.4GHz core 2 duo processor with !333MHz FSB
- Maximum system bus transport speed 1333MHz FSB
- 4GB DDR3 1066MHz RAM

Obviously here its the RAM. I'm also guessing that if its a laptop it could also potentially accommodate a maximum of 8 or 16GB (some even 32GB) of DD3 1333MHz RAM thanks to the kinds of controller chips used in such high end machines. More typically you'll see these kinds of specs as standard in the very latest top end laptops such as Macbook Pro's. You'll also find that they usually have the latest corei5's or core i7's in them.

(click here for en explanation of how many processing cores a corei7 processor actually has... Hint : its not 8)