Drupal 7.x

In which file should one best place bullshit view-related functions? like, say i have function foo($bar) which takes a string and returns a modified string, and I am going to use that functionality all throughout my site?
I placed a function like this right in node.tpl.php where i was working, just for a quick test, and it causes my webpage to crash and not render at all. Where SHOULD it go?
thanks

I am using a shared server which is currently running php version 5.2.15.

I understand that Drupal 7 requires php 5.3

I have asked by hosting company if they can help, to which they politely replied...

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Lots of scripts aren't compatible with PHP 5.3 due to all the functions they have removed so we don't offer it on our shared hosting at this time.

I'm new to drupal and looking forward to getting my feet wet. What I need to know is, is it possible to create groups or rather "organizations". I would need that organization to be a self standing entity and I would need to give user's certain permissions over it. As in there would be organization administrators and moderators, etc.

Hello all!

I need to override the 'user/%user/edit' page for a specific user role, say 'foo_role'. I have successfully created the new user registration form that explicitly selects the fields to be used in creating a new foo_role user however, because there are additional user fields not applicable to foo_role the edit page for this role is not correct.

This is my best attempt, but it fails:

I am looking to create a client access area on a site. Ideally this is how it would work.

I would set up multiple clients.
There would be a client login area.
Depending on their login details they would see pages relating to them.

E.g.

Client 1 would see pages:
Page 1a
Page 1b
Page 1c
etc.

Client 2 would see pages:
Page 2a
Page 2b
Page 2c
etc.

Is there a module that can do this or is this something that can be set up with the default installation?

Thanks