Continuity mistake: When Marty returns to 1985, he goes to his house and gets in his Toyota pick-up. Look closely behind his head when he first gets in the truck, there is no driver-side head rest. But when he picks up Jennifer, when they pull up to the stop sign the head rest is there. (01:45:00)
Continuity mistake: Watch the scene with the Indians (just as Marty sticks the DeLorean into reverse) and see the differences of how close and far the Indians are from the DeLorean. (00:18:59)
Continuity mistake: When Marty goes back from 1955 to 1885 and meets the Indians, note that none of the Indians shoots any arrows nor do any arrow hit the car. You can see that when he drives the car back into the cave. But when he gets back to the cave after the Cavalry ride, a long arrow sticks out on the side of the car. (00:18:10 - 00:20:00)
Visible crew/equipment: In the saloon scene where Doc passes out, a production light with barn doors and stand can be seen in the upper left over Marty's shoulder.
Continuity mistake: When the train is coming and is about to run over the DeLorean, the shadow of the train on the wall shows that it is only the locomotive. When the camera changes view, it is a train with freight carriages. (01:43:00)
Revealing mistake: When Marty and Shamus are sharing a meal at the dinner table, Shamus passes Marty the plate of rabbit. As Shamus hand moves away to let go of the plate, to the bottom right hand corner of the plate, a purple patch appears briefly where the two M. J. Fox actors interact, an error with the Vistaglide camera tech used back then. Easier to spot on Blu Ray Version, better than DVD. (00:24:10)
Continuity mistake: When Doc's about to send Marty back to 1885 from 1955, and Marty's dressed up...when Doc's walking back and forth loading up the car - look at the shadow from the building. You see it changes by several feet in a few seconds as the scene was obviously shot throughout the day. (00:16:35)
Revealing mistake: During the sequence with the Native Americans chasing the Delorean in the beginning, in one shot looking up at the sky you can see contrails from a plane, obviously not around in 1885. (00:19:25)
Visible crew/equipment: When Marty is with Jennifer in his new truck, as the camera cranes down to where they're talking, you can see a crewmember with a white shirt and some of the camera and crane. (01:46:10)
Visible crew/equipment: In the scene where Marty is chased out of the saloon in 1885 by Buford "Mad Dog" Tannen & his gang, in the shot showing Marty pushing his way between two women, the cameraman can be seen running along with the camera beside him to the left of the screen.
Other mistake: When the movie ends and Doc says, "It means your future hasn't been written yet," watch his son Verne behind. He stares at the camera, calls someone from the crew, waving his hand, and points at his crotch. Seemingly, the kid was having a hard time trying not to pee on himself.
Continuity mistake: While at the dance Marty is showing off at the shooting gallery. After shooting all the targets he twirls the gun and hands it back to the booth operator with the barrel in his left hand. Very the next frame shows the gun in his right hand. (00:54:28)
Visible crew/equipment: At the drive in theater, Marty says he'll put the boots on when he gets there. The camera pans to the left to follow Marty and Doc as they continue to talk. On the very far left side of the screen, the shadow of the boom mic briefly dips into frame. This happens just before Doc walks over to the DeLorean from his car.
Continuity mistake: When Marty is walking into the 1885 Hill Valley, he walks past an A. Jones manure hauler, which is embedded in shadow. In the very next shot, not only is he several more metres down from the hauler, the hauler is in sunlight. (00:27:31)
Continuity mistake: When Doc and Marty are chasing the train, first their shadow is on the left of them, then in the next shot it's on the right. (01:30:40)
Visible crew/equipment: During the party scene, towards the end when Marty and Doc are discussing the duel and the fact the train may be late, you can briefly see a PA system center left of frame (bass cab with PA head on top and above it 2 tweeters side by side) it would make sense that a PA system be on set during the scenes so the band and dancers had a soundtrack to mime/dance to. (01:01:29)
Continuity mistake: Watch as Seamus hands Marty the baby, there is a definite "jump" and Marty is facing in almost completely the wrong direction, looking for a clue from the set's crew as to where he should be looking to catch the baby from... (00:24:20)
Revealing mistake: When Marty pours the wake-up juice through the funnel into Doc's mouth, in the close-up the funnel is straight, but we can't see Doc. From a different angle where we do see the funnel stuck in his mouth, check the right side of the screen: The funnel is actually skewed (and seemingly it must have a tap) and the liquid is falling out in large amounts to prevent the actor from drinking it.
Revealing mistake: When Clara horseback rides towards the train, when she reaches for the handlebar she is replaced by a very obvious stuntwoman who looks nothing like her.
Chosen answer: Yes. A "googol" is the number 10 raised to the 100th power, or a 1 followed by 100 zeroes. A "googolplex" is an even larger number - 10 raised to the power of a "googol", or represented as 1 followed by a "googol" zeroes.
BGraz