many PDF Files are now created with Acrobat 8 (as an abs Minimum) > 10 This supports Page Streaming ??? AT LAST ! but only after ALL pages are downloaded (> delay) ie it still downloads in the background So . . . beware ! . . . it IS SO Slow!
These PDFs keep downloading in the background if you are not wary & can chew up your PC resources.
AND in VISTA if you have both Reader and Acrobat editor open or if you open. multiple PDF. . . > IE & and / or Reader CRASHES
ie PDF IS NOT PAGE SERVED whereas for example DJVU is. ( > our original “Flip” format > 10years ago but now redundant > & discontinued ! )
( but then DJVU seemed to have been unwittingly sabotaged by the original Flip owners Lizardtech / Celartem in favor of “disguised format” publishers but WE still perservered ! now evolved into various “FlipPage” formats > FlipHTML5 being the latest and most “brilliant”
Of course with cable ISDN>NBN etc these large multi-page PDF’s are now arguably less of a problem re Download speed etc
PDF Reader v.X Now Available
* Fully Text Searchable
a good page design tool but for web browsing . . . still a bit dysfunctional
the wars between Adobe & Apple and IBM PCs vs Apple and Browser incompatabilities
even Windows is not compatible with itself WIN10 in fact “a virus” ?
HTML-5 helps but the PC World is arguably an absolute mess !
Mobile phones make web-browsing a nightmare all but or simple twitters / tweats and “twats”
www.chromtech.net.au/pdf2/. . . DIR Archive > “~ALL”our PDFs but large files >20p are really TOO SLOW! to be practical in PDF
some “Archive” examples Rtx09-TechArticles_1-42.pdf PDF
original FLIP generally better with 
really are all but obsolete 
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