It comes from the Sidestep ruling: Sidestep as a similar wording ("can move up to 4 squares"), and we've been told these 4 squares were a limitation; if, for some reasons, the character using Sidestep couldn't move 4 squares (because of a speed value of 3 or less, or a speed value of 6 or less and begining its move in hindering terrain), well, it can't move the full 4 squares, and can only move up to the maximum of squares allowed by its current speed value.

SIDESTEP
• The 4 squares of movement is a limitation, not a
requirement or an ability to move more than what the
character might normally be able to move.

Charge states When you give this charactor a move action he may move up to half his speed value and then make a close combat attack as if he had been given a close combat action. Your giving him a move action when you charge the opponent and then taking a free close combat action which gives the charactor the ability to make a close combat attack. If the charactor is in hidering terrain and possesses Charge, Leap/Climb, and Stealth he may use Lunge and Running Start to charge out of hindering terrian with out incurring the half speed penalty hindering terrain provides.

Charge is a power action, not a move action.

Completely forgot they included it in the Player Guide... Much clearer than my explanation.

Obviously, you have no idea what you're talking about.

Here is the actual wording of Charge:
"Charge
Give this character a power action; halve its speed value for the action. Move this character up to its replacement speed value and then give it one close combat action as a free action. A character with this power ignores knock back."
(from the Player Guide)
It doesn't have much to do with what you just wrote.

What they did was change the nature of Charge this was a change I didn't know about. So I wasn't wrong just misinformed about the change it's a very different power when reading the IC P&A Card I keep on hand. For the most part those powers haven't changed since the game began and 99% of the time it's a spot on source.

Well, that does explain a lot of things.

Since Infinity Challenge, there have been something like 5 new rulebooks and PACs (and I don't even count the various FAQs and Errata & Clarifications documents); most of the powers have been reworded since then, some even had effects added or removed, and all of these modifications affect their mutual compatibility, as well as their interactions with feat cards, special powers, etc. ...
Saying that the Infinity Challenge PAC is spot on 99% of the time is just wrong.

For your information, the latest rulebook and PAC can be downloaded from the Units section of this very forum, and the latest Player Guide (which gathers the current FAQ and Errata & Clarifications, and also contains the current wording for all powers, team abilities, special powers, feat cards, special objects and battlefield conditions) can be found in one of the sticky thread of the Rules of Combat forum.
Please, read them.

While I'll agree that the powers haven't changed for the most part the game has undergone significant changes that drastically alter the details on powers. If I recall correctly, the IC PAC didn't even have purple powers on it, let alone brown or lime.

How actions work particularly in relation to powers, changed about 4 years ago as I recall when Universe came out (maybe it was Indy, but I don't think so). Since then, they've been refined, tweaked, and slightly adjusted.

A sample of things you wouldn't know from the IC PAC:
* Super Strength gives you +2 damage against walls and blocking terrain.
* Pulse Wave requires you to have an opposing character in range
* Support rolls only grant you d6-2 (minimum one) healing (not d6)
* Shape Change allows you to prevent being targeted on a 5 or 6, not just a 6.
* Range Combat Expert can be used with other powers - but it requires a power action to activate it and the "other" power has to accomodate that. For example, you can use Willpower in the same action (assuming you know what that is without even an Hypertime PAC) but you can't use Psychic Blast.
* Energy Explosion cannot have its damage enhanced.

And I'm not even touching the powers/team abilities that have been added/changed.

what about lunge and vault? can combine both?

Yes.

(as a bonus, here's the complete sequence for Charge + Flurry + Maneuver + Vault)