The Devil Wears Prada is a 2006 Film of the Book starring Anne Hathaway and Meryl Streep. It tells the story of a young woman named Andrea "Andy" Sachs (Hathaway). Her first job out of college is as personal assistant to a merciless fashion magazine editor, Miranda Priestly (Streep). It is loosely based on the real editor for Vogue magazine, Anna Wintour (sometimes called "Nuclear Wintour" by her detractors); see The September Issue for a documentary about the real Wintour.
This film provides examples of:
Accidental Misnaming: Andy considers it a great breakthrough when Miranda starts calling her by her own name.
Adaptation Dye-Job: Andrea, blonde (like author Lauren Weisberger) in the book, is played by the dark-haired Anne Hathaway in the film.
Denied Parody: Miranda bears a striking similarity to Vogue editor Anna Wintour, but the author maintains that she is a composite of fiction and various stories of her friends' first jobs.
Double Standard: After she warms up to Miranda, Andy points out that if Miranda were a man, people wouldn't care about her sadistic ways, only what a great job she does.
Andy is also subjected to this as she gets better at her job by her friends and boyfriend. While it's understandable to get upset over someone working overtime on a special occasion, it's another to not be able to acknowledge that she's just trying to do a one-year job so she can pay her dues and hopefully get the job she actually wants.
Enforced Method Acting: On the first day of shooting, Streep went up to a nervous Hathaway and told her, "I think you're perfect for the role and I'm so happy we're going to be working on this together. Keep this in mind, because this is the last nice thing you'll hear from me."
Friends Rent Control: Mostly averted. Andy and Nate are two recent college graduates and their apartment is only slightly nicer than what someone of their income level could realistically afford.
Hollywood Pudgy: In-universe, as a pot-shot to the fashion industry in general. Size-six Andy is considered fat at work and has to lose weight. It's also implied at one point that Miranda has postponed a photo shoot with Gwyneth Paltrow until she's lost some weight. The Gwyneth mention was due to the fact that at the time, she'd just had one of her children.
Humble Pie: After being chewed out by her boss, Andy storms out of the office and goes down to Nigel to complain. Nigel answers with a thorough "The Reason You Suck" Speech, forcing Andrea to admit that she doesn't appreciate her position enough.
Informed Judaism - Andy as well as Miranda, who changed her name to not sound Jewish in the book. These aspects are not mentioned in the film though.
Lost Aesop: The film starts off saying "Don't follow the crowd", championing Andy's uniqueness, only to reveal that her colleagues do actually know what they're talking about and she needs to catch up now she's working in the fashion industry. It then heads towards "Broaden your horizons and get to know the people you thought you had nothing in common with", changes direction and staggers towards "Don't put your job ahead of your friends" before eventually ending up somewhere in the region of "Don't compromise your ideals by working for a heartless bitch", even though doing so results in Andy getting her dream job...
To expand on the above: Andy calls Miranda out on ruining Nigel's promotion to save her own ass and that she'll never do such a thing. Miranda tells her that she already did when she went to Paris in Emily's place.
Pet the Dog: Andy calls Emily to offer her some of the clothing she was given by various designers while in Paris.
Pet Homosexual: Averted with Nigel. He does give Andy a makeover, thereby saving her from herself, and he is Tall, Dark and Snarky, but he's also much higher up the ladder than she is, as well as legitimately older and wiser, offers guidance in her career only, and doesn't hover around her like he has nothing better to do than make sure her life is running like clockwork.
The Nigel in the book is a much different character. Young, African American, and larger-than-life flamboyant (believed to based on another real person at Vogue, editor-at-large (and he is large) André Leon Talley). He also doesn't seem to connect with Andy on a meaningful level. Instead he's occasionally brought up in the book as one of the few people who can disagree with Miranda without fearing for their lives.
And in the book he is just one of several gay staffers at the magazine.
Except that Andy's not doing something righteous or standing up for some lofty principle by quitting her job, which is totally how the movie presents it.
Pretty in Mink / Fur and Loathing: The fur coats and wraps Miranda wears could go either way with this trope and might even depend on your interpretation.
Product Placement: Roughly 60% of the movie — 90% if you watch it with the DVD commentary.
"The Reason You Suck" Speech: Andy seems to get nothing but these — first from her coworkers for not taking her job seriously, then from her friends for taking her job seriously.
Thigh-High Boots: A key part of Andy's makeover is when she appears at the office wearing a chic Chanel outfit, complete with elegant black thigh boots (also by Chanel) and dazzles the other office workers.
With Friends Like These...: Andy's friends and boyfriend. They gladly accept the gifts she gives them (courtesy of her job at Runway), but in the same breath "playfully" steal her phone while it is ringing and toss it between them, with her boss on the line - an act which could easily get Andy fired.
The Woman Wearing the Queenly Mask: Miranda regrets how her high-stress lifestyle is negatively affecting the lives of her children, but acknowledges that it's a result of the choices she's made and won't complain about her own problems.
Nevertheless Miranda does give Andy the recomendation
The book provides examples of:
We All Live in America - the English Miranda is described as leaving high school in London at seventeen, three months short of graduation. In the UK, students go to secondary school, and leave at sixteen without 'graduating' (though nearly all get some qualifications- usually GCSEs- at this point; those that stay to 18 take additional qualifications for the last 2 years). Her siblings also slipped her 'bills' when they could afford it.
The term "high school" is actually in pretty common usage in the UK, with many secondary schools actually having it as part of their name. The other terms, not so much.
Depending on Miranda's exact age the official school leaving age at the time might even have been 15. Given that she was from an apparently poor East End family it is unlikely that she would have been expected (or even allowed) to stay at school beyond that. The qualifications at the time would have been CS Es or O-Levels depending on ability (at 16) and A-Levels (at 18).