Corrected entry: When Monica and Ross are discussing why they are not allowed to play football, Monica states in the story that they were both 6. This would imply they are either twins or at least the same age. However, we see that Ross is in fact older than Monica. Also, later in the scene Monica and Ross say the football incident occurred 12 years ago. This would mean that they are both currently 18 years old which is false. In one episode earlier in the season Monica states that she is 28 years old.
New this month Correction: She doesn't say they were both six, she says the event happened in "Gellerbowl 6", ie. the 6th year of the "Gellerbowl".
Corrected entry: Monica tells the guys that she and Phoebe will search the third and fourth floors for the monkey and the guys would search the first and second floors. But Monica and Phoebe knock on Mr. Heckles' door, #9, which would be on one of the lower floors.
Correction: It is impossible to know how many apartments are on each level. It is likely that Monica and Phoebe are searching on the third floor at that very moment, meaning they could be on a floor lower than theirs.
Corrected entry: When Rachel refuses the two guys she is offered, when she is about to storm out then asks the guy about his hair, the shot changes. Between these shots, Phoebe simply disappears from beside Monica and Chandler.
Correction: When the scene is cut to Monica and Chandler you can see Phoebe move over, and when you see Rachel come back, you can see Phoebe's hand on the left of the screen.
Corrected entry: Across the whole show, the infamous wall in Rachel's room / guest room (Monica's apartment) changes. When the room is not being filmed, the wall is as normal, but on quite a few episodes, when the room is actually used for scenes, the wall is much shorter. In both the episode where Ross buys Phoebe a bike, and where Phoebe and Rachel have to live with Monica after their apartment caught on fire, people are able to walk straight into the room without the wall being in the way.
Correction: Just rechecked the bike episode (the one with all the candy) and compared to season 8's the one with the stripper which shows Joey and Chandler entering the room. The camera angle from the main room is at nearly 45 degrees, the wall is not longer in that scene it is just the angle of the shot, which is the standard angle used from the main room when viewing it.
Corrected entry: When Rachel is holding the cat on the cushion with the red oven mitt, for one shot her hand changes from holding the cat, to holding the pillow.
Correction: I just watched this episode, and you can actually see her move her hand from the cat to the pillow and back again.
Corrected entry: When Chandler finds out that the video marked 'Monica' is just a football game he says, 'This may be the first time I have enjoyed football. Although in 'TOW The Football' he is quite happily watching the Thanksgiving Day game.
Correction: In TOW the Football, he is watching football to avoid helping cook dinner. He does not say he is enjoying it.
Corrected entry: The wedding is threatened because Ross, Emily, and Monica discover that the location has been torn down a few days early. However, when one plans an event, especially a wedding, one puts down a deposit to hold the location, signs a contract, and has all of that in writing. The church would not have allowed the tear-down to happen early as they'd be in breach of contract for accepting money and then allowing the church to be torn down before the wedding. And if they had broken the contract, Monica would have been screaming about it and demanding a refund.
Correction: They decided very fast to get married. They didn't have a place and they were just going to check that place. Maybe they were hoping to close the deal that day.
Corrected entry: When Monica and Chandler are in the bath, she goes under the water as Joey comes in, and when she reappears her wine glass is still full of wine. It would have filled up with water, not stayed with just wine.
Correction: When Monica surfaces, it is actually Chandler's glass which is in shot and has never been underwater. Monica's glass isn't seen again.
Corrected entry: When Alan arrives at the apartment, he doesn't have anything with him, but when Monica says goodnight to him at the door, he is carrying an umbrella.
Correction: If you look real carefully [and well, try slow-motion it] when Allan arrives he indeed has an umbrella on his right hand, the camera shot just shows a bit of it, but you can actually see it there, so him carrying an umbrella when leaving is not a mistake, because he took it in with him when he arrived.
Corrected entry: Joey is shown moving into Chandler's apartment and meeting everyone for the first time approximately one year before Rachel showed up. It is also mentioned that it is a warm time of year, indicating that it is set during the summer months. However in 'The One with All the Thanksgivings' (series 6) Joey is shown living with the Friends by Thanksgiving (i.e. November) 1992.
Correction: This entry corrects itself: Joey is shown living there BY Thanksgiving.... so he moved in during the prior summer.
Corrected entry: When Rachel is getting rid of her date to go inside and console a depressed Ross, you can see a crew member just as she opens the door when she goes back inside. That's neither Chandler nor Joey since Ross was just sitting there alone.
Correction: There is no-one else there, except Ross in the background. What you see is maybe his shirt, but nothing else.
Corrected entry: When Phoebe is reading Joey's interview in the soap magazine, her earrings change colour from red to yellow in between shots.
Correction: Actually, in some shots you can clearly see that the inside of the earrings are yellow and the outside is red so it is not a mistake.
Corrected entry: In Season 2 Episode 1 'TOW Ross' New Girlfriend' Joey is talking about how his tailor did his first pants when he was either 15 or 16. He wasn't sure and said 'When was 1990?' Indicating that he was 15 or 16 in 1990. In Season 6 Episode 19 'TOW Joey's Fridge' It was revealed that in 1981 Joey was 13. Which means that Joey was born in 1968. If Joey was born in 1968, then in 1990 he was 22.
Correction: He never says that in 1990 he was 16. He was asking when was 1990 to have a time reference, and then calculate when the event happened in relation to that.
Corrected entry: Even though Chandler and Phoebe say they don't really watch the football game, it seems as though they agree that Detroit Lions won the game. But the 2001 Thanksgiving Day game between the Lions and the Packers were indeed won by the Packers.
Correction: You missed the whole point - they say they don't watch the game and then they guessed the wrong winning team.
Corrected entry: Phoebe says that her Grandma gave the cookie recipe to her 'on her deathbed', yet in series 5 Phoebe says that her grandmother died suddenly on a shopping trip, rather than from a long illness or old age as she suggests.
Correction: People generally have two grandmothers. Just because her father ran off, doesn't mean that his mother abandoned her grandchildren so readily.
Corrected entry: At the point where Monica Geller shows Joey the DVD, it's not a DVD but a board to show Matt Leblanc his lines (note him moving his eyebrows).
Correction: Conjecture. Joey is a "dim bulb" and he is reacting to the situation. There is no indication that Matt LeBlanc would need cheatsheets to remember his lines.
Corrected entry: When Monica Geller tries to get a rematch on the race, Chandler Bing says they left -- but no door sound was heard.
Correction: Just because you don't hear a door close doesn't mean it didn't. They were playing a game and cheering and carrying on so it is perfectly conceivable that people could leave without being noticed.