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  The  testing  process 

 A structured testing process is necessary in order to identify and solve as many problems as 

possible before the system is released to users. This testing is conducted in a structured way 

by using a  

test specifi cation

  which is a comprehensive specification of testing in all modules 

of the system. If the  use-  case method of analysis described in  Chapter   11    is used then it will 

specify the different  use-  cases or scenarios to be tested in detailed test scripts. The compre-

hensive testing specification will also cover all the different types of test outlined in  Table   12.1   .    

 Testing in the web environment requires new constraints. Unfortunately the list of con-

straints is long and sometimes neglected, to disastrous effect. Retailer  Boo.com  used a com-

plex graphic to display clothes that was too  time-  consuming to use for visitors to the site. If 

there are a thousand potential users of an e-commerce site, all of the following constraints on 

design may exclude a proportion: 

   

● 

   Speed of access  – everyone has used sites with huge graphics that take minutes to down-

load. Good designers will optimise graphics for speed and then test using a slow modem 

across phone lines. Yahoo! downloads in just one second, so this is the performance that 

users expect from other sites.  

  

● 

   Screen resolutions  – designing for diff erent screen resolutions is necessary since some 

users with laptops may be operating at low resolution such as 640 by 480 pixels, the major-

ity at 800 by 600 pixels, a few at higher resolutions of 1064 by 768 pixels or greater. If the 

designers have designed the site using PCs with high resolutions, they may be diffi  cult to 

read for the majority.  

  

● 

   Number of colours  – some users may have monitors capable of displaying 16 million col-

ours giving  photo-  realism while others may only have the PC set up to display 256 colours.  

  

● 

   Changing font size  – choosing large fonts on some sites causes unsightly overlap between 

the diff erent design elements – depends on the type of web browser used.  

  

● 

   Diff erent browsers  and diff erent versions of browsers may display graphics or text slightly 

diff erently or process JavaScript diff erently, so it is essential to test on a range of browser 

platforms.  

  Testing

  Testing 

  Aims  to  identify 

 non-  conformance 

in the requirements 

specification and errors.