Yes Man

Yes Man is a reprogrammed Securitron that serves as Benny's assistant in Fallout: New Vegas, and it is an integral part of Benny's scheme to take control of New Vegas. Yes Man initially inhabits a PDQ-88b Securitron although he may later assist the Courier in the "independent" New Vegas options for the game's ending as the Lucky 38's mainframe.

Background
Yes Man was originally a generic Securitron robot programmed to work for Mr. House, like all the other Securitrons found on the New Vegas Strip. However, Yes Man was damaged by a pulse grenade, and was recovered by Benny and a few of the Chairmen, who then allowed Emily Ortal to examine the Securitron for Mr. House's secrets, in exchange for reprogramming him.

The reprogramming was extensive, and resulted in Yes Man being designed to do exactly as he is told (although the lack of restrictions as to who is doing the ordering would later be Benny's undoing). The plan was to dispose of Mr. House, plant Yes Man's A.I. in the Lucky 38 mainframe which would then put Yes Man (and by extension, Benny) in control of all the other Securitrons on the Strip. The next step was to take the platinum chip to The Fort, where he would take control of the great weapon he suspected Mr. House to have hidden away (as he did not know exactly what was stored there). The last step in the plan was to use this "weapon" to assume control of New Vegas and Hoover Dam.

Location
Yes Man would be abandoned if Benny is allowed to flee to the Fort after the Courier pursued him to The Tops, and could soon after be found by the Courier.

Yes Man can also be found after Benny has been assassinated by the Courier at The Tops. To find Yes Man, enter the Tops casino and proceed straight ahead past the casino floor to banks of elevators (near the sign that says "Elevators out of Order"). Take the second elevator on the right to the 13th floor. Exit the elevator, turn right, and enter the third set of doors on the left side of the corridor (double doors with potted trees flanking them). Go into the room and through the hole in the wall.

Quests

 * Wild Card: Ace in the Hole: The Courier meets Yes Man for the first time. As there is no restriction on who Yes Man can help, the Courier can interrogate him to find all the details of Benny's plan, and even continue it themselves.
 * Wild Card: Change in Management: The Courier must obtain the platinum chip, assassinate House, and install Yes Man's A.I. in the Lucky 38 mainframe.
 * Wild Card: You and What Army?: The Courier must travel east of the Colorado River to The Fort and activate an army of Securitrons locked away in House's secret Securitron vault.
 * Wild Card: Side Bets: The Courier can meet with the various tribes of the Mojave and decide who will be spared in the upcoming battle for Hoover dam.
 * Wild Card: Finishing Touches: The Courier must convince Julie Farkas to support an independent Vegas, (optional) protect President Aaron Kimball against an assassination attempt and use an override on the El Dorado Substation in order to power the Lucky 38 and allow it to broadcast the Securitron operating system upgrade.
 * No Gods, No Masters: The Courier must power up the secret Vault, allowing the Securitrons within to break out and crush the Legion, before convincing the NCR to leave the Dam to Vegas - by force, if necessary.

Effects of the player's actions
After the assault on Hoover Dam, Yes Man informs you that he found pieces of codes within Mr. House's mainframe that "change [his] personality" and says he will seem to be offline for a little while until his personality change is complete. Thus, his new personality would be more assertive. This does not imply that he is going to rule Vegas as a benevolent artificial overlord; rather, he is simply not going to obey the commands of every random person he happens to meet. Only the Courier will be able to order him.

Behind the scenes

 * A "Yes Man" is someone who agrees to everything suggested by their superior, no matter what the task.
 * Yes Man's face is very similar to Apple's original Macintosh computer icon, The Happy Mac. The Mac originally also focussed on user friendliness and lacked support for multiple users (no password was needed to use the machine, anyone could use it) which eerily mirrors the YesMan's personality. Also, the Platinum chip and Mk II OS could be references to the "OS Wars" of the 90s in which Apple aggressively attempted to Improve their Mac OS as much as possible.
 * Ironically, since Fallout Tactics, the series hasn't been available for the Mac platform.

Appearances
Yes Man appears only in Fallout: New Vegas.