With increasing use of the computers in our lives, the number of situations where one finds the need for a computer is continuing to grow. Clearly, not every such situation will be in the vicinity of a computer. Enter Laptop to the rescue! Laptop computers have given us the enormous advantage of literally carrying around with us in our hands a great deal of computing power to the situation rather than bring the situation to the computer.

Laptops are particularly handy for those that travel frequently and for those that find themselves needing to convey large amounts of information to an audience such as with a presentation. It is also extremely useful for professional technical staff that has to troubleshoot and maintain electronic equipment that is spread about in the field (e.g., telephone network equipment). Lately, Laptops are becoming increasingly useful to students and academicians where it helps to efficiently collect and organize a lot of study material (such as in a library). And as Laptops become increasingly powerful and increasingly affordable, the very notion of a Laptop of being just a companion to a ‘home’ Desktop is being challenged.

While Laptops are a very useful device, they do have limitations that will likely prevent them from taking over the Desktop world. In this article we examine a few of these ‘limitations’ and outline some important tips for the selection of a Laptop.

This article also includes a section on a more recent introduction to the computing world – the PDA – which stands for Personal Digital Assistant. PDA is to a Laptop what Laptop is to a Desktop computer. Meaning, just as a Laptop is a ‘limited version’ of a Desktop computer but with increased portability, PDA can be seen as a ‘limited version’ of a Laptop with even more portability. With the risk of confusing the non-technical reader, it would be no exaggeration to say that with constant advancement in computer hardware and software technologies, the boundaries between these devices will continue to diminish other than in physical size and in ergonomic factors such as the way a human interacts with them (e.g., keyboard/mouse vs. stylus).

Anatomy of a Computer

A high-level simplistic view of a modern-day home computer is shown in the figure below.

The main components are:

  • Processor (the main engine of the computer)
  • Memory (where the software ‘brains’ of the computer as well as data are stored – as long as the computer is powered ON)
  • Mass Storage (where user files, application software, etc. are stored permanently – meaning, they are there regardless of whether the computer is ON or OFF)
  • Removable Storage (used to transfer files in and out of the computer on a need basis)
  • Peripheral controller/adapter  (that controls and provides all interfaces to the computer’s peripheral devices including the monitor, keyboard, mouse, printer, removable storage, USB ports, etc.)

Any computer – Desktop or Laptop – has these basic components. The difference really is in the way each of these components is designed and implemented. The constraints placed in the implementation of these components in a Laptop are driven by the most desired characteristics in a Laptop, which are:

  • It should be small – smaller the better.
  • It should be light – lighter the better
  • It should be powered by a battery
  • The battery should last a long time. After all, who wants a Laptop that would not run even for 5 minutes without needing to be plugged into a power outlet
  • It should not generate too much heat – you don’t want to burn your lap, would you?
  • It should allow the user to use floppy disks or CDs or other forms of ‘removable’ media so that files can be transferred in and out of the computer

Not asking for a lot are we? But surprisingly, most Laptops available in the market these days offer just about all the above. If that is the case, what is the problem? The problem comes as always, when scrutinizing details. Laptops achieve the above characteristics by compromising on the physical size and features of the various building blocks shown in the above figure. This compromise varies from manufacturer to manufacturer and hence the variety of Laptops in the market. Further, the compromised set of components are packed together tighter than in a Desktop, making Laptops less rugged than Desktops from a physical handling standpoint.

Examples of the ‘compromise’ are:

  • Using 10GB hard disk rather than a 80GB hard disk that is commonly found on a Desktop
  • Supporting 2 USB ports rather than 6 USB ports that are commonly found on Desktops
  • Not supporting built-in CD-ROM or DVD-ROM drives but offering those as devices that can be attached to the USB port when needed. Desktops generally have these built-in.
  • Not supporting user-installation of components such as additional memory modules. Desktops allow for user installation of components.

If there is one ‘Achilles heel’ for a Laptop, it is the battery. ‘Battery life’ is a critical factor to be looked at before deciding to buy a Laptop since the very purpose of a Laptop is for it to be a portable computing device that can operate for a long enough period of time for you to get your job done before searching for a power outlet to plug it into.

Tips for Laptop selection and use:

  1. Procuring well-known brands (Dell, IBM, Sony, Toshiba, etc.) as opposed to ‘clones’ is an important factor. Servicing a Laptop often requires special tools and training and hence the importance of this factor. Further, Laptop replacement parts are not readily available as are those for Desktops.
  2. Don’t look to the Laptop to replace your Desktop by adding more and more features into the package. Remember, the purpose of a Laptop is convenience of portability. Having said this, one feature you want to maximize is memory.
  3. Look for the lightest possible package. While a technical specification of 3.5 lbs may seem only marginally heavier than 2.8 lbs, the difference will start to weigh-in when you go from gate to gate at an airport or from platform to platform at a train station.
  4. If you must, compromise on not having built-in Floppy disk, CD-ROM or DVD-ROM drives. You can always procure such devices that are USB compatible and connect them when needed. Such additional devices don’t have to be lugged around every time but only when you anticipate their need.
  5. Maximize the system memory and hard disk size you can obtain. 128MB of memory with at least 10GB of hard disk is recommended.
  6. Don’t look to maximize processor speed. Power consumption (and therefore battery life) is dependent on the processor speed. Processor speed of 500MHz should suffice for most applications. Here you would likely be driven by cost and availability. With time, lower processor speeds are generally phased out and not available. Conversely, the highest available speed processors are generally a few notches more expensive than ones that are speed-wise just a notch lower.
  7. Look for Laptops that do not have fans. Fans are amongst the most vulnerable points of failure in a Laptop.
  8. Look for Laptops that have at least one and preferably two USB ports. USB is one of the most versatile interfaces that computers can have at the present time.
  9. Make sure Laptop has at least one PC Card (also called PCMCIA) or Cardbus slot. This will allow you to add a variety of adapters (such as a Ethernet network adapter, a modem, etc.).
  10. Having a built-in Infrared port may be useful on occasions but with increasing use of wireless connectivity in the computer world, Infrared port interface is not that important anymore.

And as for using your Laptop:

  1. Be ‘gentler’ when handling your Laptop. It is not as rugged as your Desktop. Do not leave it for any length of time under direct sunlight or any other source of heat.
  2. Backup the data on your Laptop frequently. Hard disk ‘crashes’ are a higher probability event in a Laptop when compared to a Desktop.

Personal Digital Assistant (PDA)

Origin of PDA can be traced to electronic Organizers that hit the market in the ‘80s. Initially PDAs were an extension of those organizers in terms of capabilities. They were devices for storage of personal information such as contact lists and appointments. But unlike organizers which were stand-alone devices, PDAs were meant to be used as a companion device to a Personal Computer. They connected to Personal Computers and ‘synchronized’ their information to the one on the Personal Computer. This enabled people to carry with them in a very compact form, important information on their Personal Computer. PDAs were and still for the most part are small battery operated devices like Organizers meant to be carried around in a shirt pocket.

While the basic concept of a PDA remains pretty much the same, with advances in technology, PDAs are fast becoming relatively capable computing devices. You can now download software into them, play games, connect to the Internet wirelessly and more. Still, from a processing power standpoint, they lack the punch of a Laptop.  Increasingly, ‘Pocket’ versions of regular applications like Word, Excel, Quicken and other popular software are becoming available. But having said that, these pocket versions are relatively weak and offer nowhere near the capability of their ‘regular’ versions.

PDAs with wireless connectivity to the Internet may seem like a very powerful device to have. But the reality is that pocket Internet Explorer running on even the latest PDA cannot process all data available on a website. Not to mention the small screen on which the user will be viewing that information. Access email on the road is touted as a very useful feature on PDAs.  But there again, handling attachments to emails is a problem.

So, are PDAs worth it? The answer depends on your intended use. Using PDA as a companion to your Personal Computer is definitely worth it if you need access to a lot of information at your fingertips. But using it as a mobile computing device – like a Laptop – will likely be unsatisfactory.  There is a large variety of PDAs available in the market, in a wide range of prices. Some high-end PDAs cost as much as a low-end Laptop. If your target use is as mentioned above – as a companion to a Personal Computer, then it would not be worth it to go in for a high-end PDA.

Two families

There are two families of PDAs available in the market. One based on Palm OS and the other based on Windows (latest version is called Pocket PC). Palm OS PDAs were the ‘original’ PDAs if we can indulge in that term. They are still the more popular ones and hence have more software applications and other support devices. However, with the clout of Microsoft, Compaq/HP behind it, Pocket PC based PDAs are catching up fast.

This battle-field is an ever changing one and so do your homework before deciding which family to go with.

A word on ‘Combo’ devices

Many PDA manufacturers have recently introduced ‘combo’ devices that double up as cell phones as well. While on the surface, this seems like a nice concept it is not necessarily a very practical one. For example, not all cell phone service providers may offer the combo device. You may therefore be tied to one provider. Ergonomically, a combo device may not be best as a cell phone. Battery life may become an issue especially if you use the cell phone function a lot. Combo devices often do not have the same expandability as a dedicated device (support of expansion slots, etc.).

Tips for buying PDA:

  1. Determine your intended use. Identify the key software applications that you need. Determine if Palm OS or Pocket PC is the right platform for those applications.
  2. Once the platform has been determined, shop for PDAs that have at least 8MB of memory. Since PDAs do not have any mass storage device such as a hard disk, everything that needs to be in the PDA – including software applications – have to be stored in its memory. So, the more the memory the better you can put your PDA to use.
  3. It would help to have a PDA that has a Compact Flash expansion slot for adding more memory and other peripheral devices such as a wireless modem.
  4. It would also be helpful to have multimedia support on your PDA. This way, you can use your PDA for example as a MP3 player, or a voice memo recorder and so on.

Desktop, Laptop and a PDA?

This answered to that question is ‘depends on your need’. The combination of a Desktop and a good PDA may suffice for many. But for those that need computing power on the road – like the need to make presentations, or the need to write reports, then a PDA will likely not suffice and a Laptop may be in order. The first and most important step in selecting which combination of these devices – if not all of them – that one needs to possess is to determine one’s functional needs and the software applications (and hardware peripheral devices) that are required for those functions. That determination drives the selection.

It helps to remember that in the computer world – it is best not to buy a device until one really needs it since one can always obtain devices with more functionality at the same or lower cost a few months down the road. This is by no means to suggest an indefinite wait but merely to remind the user to make a judicious purchase.

Author & Editor: Krish Narasimhan; apt #19F, Andover. Contact by email: [email protected]. Feedback including suggestions for other topics, and contributions welcome