Cam Follower!...??

[WILLZIE]

Can someone please clear up for me what this cam follower business is about, whats the reason for change?.
Seeing a few posts where people just change them! isn't this a major job?
And is it just the one or are they changed in multiple?

Thanks.

[muckipup]

Does Carl's 'how to' guide help?:  http://www.mk5golfgti.co.uk/forum/index.php/topic,8339.0.html