Is it socially acceptable for individuals to wear clothing typically associated with the opposite gender? What are some reasons for or against this practice?

There are many reasons. This can be broken down into the eight broad categories below, though most people only think of no.6:

4) Entertainers.

If it’s merely your sexual fetish — see 3) above — don’t do it in public. You’ll look ridiculous and possible offend decency laws.

In the last 500 years, have there been civilizations whose cruelty matched that of Nazi Germany?

d) Stunt doubles.

b) In light entertainment: female impersonators/comedians; pantomime dames in British theatre.

c) Drag queens and Drag kings – an exaggerated satirical sub-section of the light entertainment field.

Why do I get stressed when I go to bed?

Don’t do it unless you want to.

Ignore people who will quote their religion at you (unless it’s your religion too).

If you’re going to do it, do it 100% and do it well. You’ll enjoy it all the more and so will the people around you. It’s often good for a round of applause or a free drink.

Police arrest roughly 60 protesters outside US Capitol - CNN

7) Transsexuals – for many of them the cross-dressing is merely an incidental stage in their transition of identity. Once achieved, the wearing of the clothes of the other sex becomes the norm, and can no longer be called crossdressing.

8) Those forced into crossdressing. This category is included for completeness but barely seems to exist in real life today. It was however observed in the period 1850-1950 when boys were occasionally forced into girls' clothes as a punishment at school or in the home. It is a staple of fiction – to escape from danger (Some Like It Hot), to obtain a job (Tootsie, Mrs Doubtfire), or forced by a sadistic female relative (much transvestite erotic fiction).

In Lancaster County, Pennsylvania or Salt Lake City it won’t be accepted. In Rio or Douarnenez at Mardi Gras it’s practically compulsory. (Seriously, I counted the men in skirts in a bar in Douarnenez: one in six.)

Why do people hate fat people so much, even people who aren't exactly supermodels themselves? It seems like such a deep, passionate hatred, like they're offended by fat people just existing. Fat people didn't do anything to them, so why hate them?

Socially acceptable? It depends on which bit of society you live in.

Don’t do it in places where it’s illegal, like Russia.

3) Fetish crossdressers - who use clothes as a substitute for, or an essential precursor to, sex. This is commonest among teenage boys, but usually disappears or develops into transvestism later. It is rarely seen in public, although the word "fetish" is often misapplied by those who should know better.

Why do siblings (or other close relatives) stop visiting each other as they grow older? Why does this happen with so many people nowadays?

a) In serious entertainment, actors playing a role. From Mark Rylance as Cleopatra or Judi Dench as Olivia to Antony Perkins in Psycho. Japanese Kabuki and Nō players. Sopranos singing "breeches" roles in opera.

2) Fashion crossdressers - some metrosexuals and most women fall into this category. Women in trousers – seen as a sexual and social aberration in 1900 – had become the norm by 2000.

Reasons against it? Basically,

What is one thing you've learned from life?

5) Other professionals: the occasional spy/undercover policeman/criminal in disguise. Gay prostitutes.

1) Occasional crossdressers - Hallowe'en, practical jokers, fancy dress parties, students' rags... etc.

6) Transvestites – what most people first think of. For transvestites, crossdressing is an end in itself; motives many and various. For most, these go back to childhood or before birth and are obsessive.

Why do women need to wear bras, in spite of the fact that the breasts are an integral part of the body?