3.5 to pathfinder, differences

[Raezeman]

Greetings,

I have been playing d&d 3.5 for two years now, but soon i might get the chance to start playing with a complete new group that plays pathfinder. I have the pathfinder core rulebook at my disposal, but not all the time in the world, so question:
What is the biggest difference between 3.5 and pathfinder i need to know, aka, what chapters do i certainly need to read thoroughly to avoid mistakes? Keep in mind that for now i will stick to core only, and plan on taking either fighter, barbarian or cleric. Not sure what race yet either.

[nobodez]

The combat chapter has, IIRC, most of the changes (combat maneuvers). You'll also want to review your race, class, skills, and feats (obviously). If you play a cleric, make sure to examine the spells and channeling feats.

[Drachasor]

It's a lot like the 3.0 to 3.5 changes. There are many changes all over the place. Feats, Skills, spells, combat, etc. Heck, there are probably more changes than 3.0 to 3.5. So you can't really sum them up.

Best advice is to read everything in PF that you will use or will come up, because there's a good chance there's been a tweak or change.

If you really want to get into how the Dev's see the game, you could then read all the FAQs where they basically have pseudo-errata, but that's a mess to wade through and I recommend going with just what is in the books.

[Psyren]

There is no single big change, just a host of smaller (yet just as important) ones that you will have to be aware of. This goes triple if you play Cleric, since you'll have to read through the spells and wrap your head around how domains and channel energy work now.

Even if you have the books, this website (http://www.d20pfsrd.com/classes/core-classes/cleric) is your friend.

The PF Conversion Guide (http://paizo.com/products/btpy89m6?Pathfinder-Roleplaying-Game-Conversion-Guide) is free and is a quick primer on the changes.