Historically, items have been a part of builds, and it's part of normal convention, because feats and skills and such depend on what items you have, and many builds depend on key items and magical items. You don't include most items, just the ones needed for some key functions.
This isn't true in all systems, as some systems don't see items as important, but is certainly very true for Pathfinder and D&D, and examples are presented for both below.
A reasonably common definition would be that a character build is the set of mechanical traits a character has that allows them to perform well at a stated task. This includes feats, skills, attributes, items, and a variety of other things.
Here's an example of that definition online.
In video game terms, your character's "build" is the arrangement of
stat points and/or gear for your character that will allow you to
achieve the best results for your playstyle. This only applies to
games where it is impossible to max out all your stats, or if you want
to stay at a certain level.
For example, here, an early build for a wish wizard is presented which relies on a magical item.
This character manipulated several loopholes in the laws of magic to
devestate his enemies and survive his brother's magical powers. By
casting Wishes out of a custom Ring of Infinite wishes created by
Spell-like Wishes from powerful Outsiders (which, as spell-like
abilities, can create magic items at no XP or GP cost to the caster,
and as Wishes, require no feats to create).
Mostly, he just Wishes his problems away by emulating a vast array of
potential spells with Wish.
High-end effects are cast from Divinely Quickened Scrolls created by
Or this build for killing a tarrasque, which relies on scrolls and such.
Summary. Cost: 17250gp - +1 mithril chain shirt of speed 6000gp -
necklace of karma bead 5100gp - bracers of archery 500gp - mighty
composite +4 longbow 1125gp - scroll of maximized cats-grace 700gp
- scroll of polymorph 700gp - scroll of improved invisibility 325gp - scroll of fly 100gp - scroll of expeditious retreat (caster
level 4) various cleric spells - free 28825gp - Miracle finisher
28850gp for equipment we should have anyway, 2950gp for scrolls, and
28825gp for the Miracle finisher... Summary: If you're going to build your D&D character into a one-man army, this is the way to go.
Looking at a more recent example, are items included?
So I am looking for suggestions on how to increase that since I see
the character being more of the in your face duelist type even though
ranged would probably be easier with a handful of archery feats like
Rapid Shot, Many Shot, and the like. So far I'm juggling with the idea
of losing the buckler to make use of Fencing Grace for dex to damage,
or just dipping a couple levels into Unchained Rogue, getting a couple
sneak attack die and dex to damage that way. Is it worth losing 3
levels of spell progression though and delaying the increase to my
bonus from Archaeologist's Luck?
So yes, items are included. What's not included normally are more roleplay based aspects, but items are a key mechanical part of your character and so are included in any build.