Oh I do want to qualify something
When it's a none super security issue - like access to this forum - you're not likely to attract hackers/spammers so the same password for training and access here can work.
When its something like Paypal, Adwords - something that involves a credit card -
PLEASE have different passwords and make them difficult to guess.
Unfortunately I know of too many stories of people being hacked into - and it's awful for them - as literally the hackers steal from them.
I'd also suggest (and if these are terms you do not recognise - then no need to worry at this stage) for Squidoo and Hub you also pick different passwords - as I also know of stories of people being hacked there and having all their affiliate links changed to the hackers and being blocked out.
This is not to scare monger - it's more about being cautious.
I use different passwords for different entities just so that I am being careful. I'd encourage you to do the same.
Caro