On Keyboard Centricity: POS system in DOS.<p><pre><code>      1. C:\&gt; a                                    {enter}
      (a.bat starts c:\pos\pos.exe)
      
      2. Pull-down menu: Transactions -&gt; Sales     {enter}
      (Sales is the default selection)

      3. Bill no: &lt;last + 1&gt;                       {enter}
      (new id starts a new bill)

      4. Item code: &lt;4823&gt;                         {4-digits+enter}
      5. Quantity: &lt;2&gt;                             {2-digits+enter}

      6. Item code: &lt;blank&gt;                        {enter}
      (just one item; give blank to exit)

      7. Menu: [Print, Next Bill]                  {enter}
      (Print is default selection)

      (loops back to 4, keying in a new bill)
    </code></pre>
Without a barcode scanner, a keyboard-centric interface takes the minimum possible number of keystrokes for a POS system. This efficiency was the norm in DOS-based text-centric systems, but with today&#x27;s GUI interfaces, developers have to put extra effort to make things keyboard friendly. This is not done well enough in many cases, and is an instance of how the forced-advancement of technology makes things worse.