I here people talking about this a fair bit, but never really understood what causes it, is it a client problem or something with the isps network

The isp can only handle so many. Some catergorize packets by type and prioritize them e.g. http gets top priority and p2p gets bottom - p2p gets dropped so that http can go through.

packet loss is where data packets go missing for whatever reason.  Sometimes its due to network design, or more frequently its a degraded/damaged cable causing the signal to be weak.  When the signal is weak fairly obviously packets just disappear into the ether.  in some cases its actually built to happen as well.  

Some network protocols have no way to recover lost packets, others like TCP/IP do by using requests.  Whichever way you look at it the signal integrity will fall down, and youll usually notice it by slow loading webpages, or stuttering streaming video.  

cheers for the anwsers that cleared that up for me

Signal loss (attenuation), interferance, link failure, cable fault, your switches/routers being to intellegant for their own good and starting to drop packets when bandwidth is being exceeded leading to to buffer overflow.

ninjas, or pirates....

sometimes pirate ninjas if youre really unlucky.

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<----Cat pirate ninjas if you are incredibly unlucky...

omg serious your banned from my thread for changing the subject !

 

/Catpirateninja stealorz Bacon packetz        

Mmmm tasteh bacon