purchase is logged in store. Thirdly, the cost of maintaining the hardware and software 

for  such  a  huge  amount  of  data  would  have  to  be  passed  down  to  the  proprietors, 

something  which  would  likely  discourage  smaller  businesses  from  taking  advantage  of 

the service. 

All  things  considered,  it  makes  more  sense  to  have  each  advertiser  sort  out  their  own 

hosting  solution  and  make  available  a  single  file  which  can  be  requested  from  (and 

perhaps still cached in) the central web server.  

4.3 Front end implementation 

4.3.1 The  GUIs  

In  the  world  of  web  development,  the  GUI  of  course  refers  to  HTML.  What  makes 

describing  the  HTML  somewhat  complicated  when  dealing  with  PHP  is  that  it  is  often 

difficult to tell where the PHP ends and the HTML begins. By definition, every line of 

PHP that begins with the command  echo  or  print  is an indicator that something will 

be output to the HTML document and hence to the user`s screen at that point. 

When designing the page, it was important to keep in mind at all times that, especially for 

a web service such as the Golden Pages, the page is very much a tool. As such, its layout 

should  be  as  intuitive  as  possible,  or  at  least  give  enough  information  back  to  the  user 

without drowning him or her in a sea of links and forms and buttons. While the interface 

is  slightly  more  complex  than  the  current  Golden  Pages  site,  it  is  certainly  no  more 

complex than the  inbox  page of an internet mail website such as Hotmail. 

It  is  also  important  to  make  the  page  some  way visually appealing. While queries.php 

has a only a minimal amount of images (five unique image files, in all) to help loading 

time, simple things such as alternating background colours for different panels serve to 

draw  the  user`s  attention  to  the  functionality  in  different  parts  of  the  page.  All  of  the 

block elements (denoted by the 
 tag in HTML) which contain the main search form, 

the   smart  form ,  the   Related  categories   panel  and  an  invisible  placeholder  for  the 

results  table  are   absolutely   positioned.  This  means  that  their  position  on  the  page, 

height and width are CSS values, which can be precisely specified to the nearest pixel. As 

well  as  making  the  page  neater,  they  also  serve  as  an  effective  replacement  for  tables 

used for layout (see the section on client side technologies above). 

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