I've recently been editing out things such as "hope this helps" and "good luck" from posts and was wondering if that crosses the imaginary line that seems to not exist in the scattered mess of questions on things that should be removed from posts.
So, let's build a neat community wiki with a list of everything (with brownie point for adding why). Please feel free to improve explanations or add other things that have been discussed.
What things should I keep out of my posts and titles?
There are plenty of things out there that users add to posts that make them harder to read by adding useless information and text that doesn't add anything at all to the post. Some other things should be removed for alternate reasons as well, but keeping the post straight-forward and on-topic is the key goal.
Salutations, Signatures, and Taglines
There are plenty of different ways people add in extra little lines that more or less act as salutations and signatures. From basic things like saying "hello", "good morning/evening", "thanks in advance", and "you're welcome" to more subtle things like "hope this helps", "I found a solution", and "this may be late but..." or "I know this is a really old question, but..." in answers, these small phrases do not contribute to the long-term value of the knowledge Stack Exchange knowledge base, and only add extra text that that may not be related or useful to the reader.
As well, any kind of personal contact information should never be included in the body of a post.
Excess White-Space (Both Vertical and Horizontal)
Extra white space that is not needed extends the page and creates unnecessary scrollbars that make viewing and analyzing code much more difficult and inconvenient. A common example showing two versions of this is seen below:
$var1 = 1;
$var2 = 2;
$var3 = 3; // Now this line will cause a horizontal scrollbar with even fewer characters...
In this example, the extra line in between each line of code is useless. It only serves to add extra lines, while normally line breaks should separate blocks of code within a program that relate to each other. As well, the indentation of the last line makes no sense and creates a horizontal scrollbar. Re-indenting to match the rest of the code is appropriate. Be cautious when editing out white-space from posts, though, to make sure that the white-space you're removing is not relevant to the code. If unsure, ask the OP or leave it for someone else to deal with.
Comments, Comments, Comments
Keep comments in the comments. Don't reply to other users' comments by editing your response into your post. Only edit in relevant information that improves your question or answer. Editing in a notice asking why people are downvoting your question is never an appropriate thing to do.
Offers of Financial Reward
This is not the place for hiring someone to do work for you, even for the simplest of tasks. You are not allowed to offer any sort of financial compensation for answering any questions here. If you need someone to build an entire website or do some other form of contract work for you, try posting an ad on a site built for this purpose. Usually the question is still salvageable by just removing the references of the reward, so pay close attention to not remove vital parts.
Degradation of Self or Others
Most often this occurs with users calling themselves "noobs". Everyone has to start somewhere, we were all "noobs" at one time, and it doesn't belong in the question. Of course, calling someone else a noob (or equivalent) is not appropriate either. Similarly, using things like "I'm an idiot" aren't great.
Continuing of degradation, the FAQ clearly states you should be nice and treats others with respect. The use of words such as f*** and b**** (yes, I censored them) are not appropriate and definitely would not be considered "being nice" by anyone (see Are expletives (cursing, swear words or vulgar language) allowed on SE sites?). Even calling someone "stupid" can be considered offensive and can result in disciplinary action.
Rants, frustration, and time spent on the problem
For example: "I've been working on this for 3 days and I can't believe this isn't simpler."
We can appreciate that you're frustrated, but if what you're writing isn't helpful towards solving the problem, remove it. And keep in mind that the vast majority of users here are volunteers; negativity will turn people away.
My Apologies
Apologizing for asking a question is a sure-fire way for people to not take it as seriously. If there's a duplicate question out there or you asked in the wrong place, it will get closed as a duplicate or people will help you find the right place to ask. If you're not a native English speaker, try your best. Eventually someone will see your question and care enough to fix it up so that it is readable to anyone.
Religion or Other Beliefs
If you're not answering a question specifically about religion on a religion-related Stack Exchange site, chances are it has no place in your content. Religion has caused wars in the real world and we're not here to start any of those. If the religious content is not directly related to the question at hand, it should be left out. This also means not using religion as examples for a question. For example, if you were building a function for a religious website, you should change your code to remove any mentions of religion in the function in order to avoid conflict here. Remember that your problem should be helpful and useful to anyone who might have a similar problem in the future.
Personal Identifying Information and other sensitive data
For example:
If you need to provide information/code/data about a project in your question, triple check that you've scrubbed all of that information out first. Redact logins, use dummy data, etc. If your question requires talking about people, use fake names or a placeholder like "Person A". When giving your location is required, only be as specific as necessary to answer your question.
Note that this information will remain in a post's edit history if you don't edit it out within the first five minutes.
Changelogs
For example: "EDIT: added more info as requested in comments"
You don't need to tell people what you changed. There's a real changelog (revision history) that's visible to everyone upon clicking the edit card/link under a post, which takes you to the post's /revisions sub-page. And people who are following the post will get notifications about edits to the post.
Non-Organic Tags
Tags in the title are perfectly acceptable as long as they get worked into the title appropriately and become a part of the actual question. Explicitly labeling the question with a tag at the beginning or end of the title by using the [tag] format or just separating the name of the tag from the question with a dash (or other character) is not acceptable. The question already has tagging features and it should be listed there instead.
Solved or Closed
If your question is solved, then accept an answer and be done with it. Appending something such as [solved] or [closed] to the end of the title is inappropriate as any question which has an accepted answer will already be visually indicated as such in the questions list.
If you found the answer to your question elsewhere and no longer need assistance from the community, consider posting that answer yourself and accepting it so that you can help others who run across your question. Or, if the answer you found was on the same site, consider flagging your question for closure as a duplicate. Similarly, if your question was answered in the comments, you can try asking that person politely to expand their comment into an answer. If that fails, you can post your own answer to expand on it yourself to indicate exactly how you used the comment to solve your problem.
Interjections
Including "Desperate!" or "Help!" in your title will not make responses any faster - in fact, it's a sure-fire way to annoy potential answerers. Focus on making your question worth reading and answering instead.
Vulgar language
On sites that accept questions about vulgar language (e.g. English Language and Usage), vulgar language should be censored out of the title.
Spoilers
It's best practice to keep spoilers for recent releases out of titles. This prevents spoilers from being shown across the network on the Hot Network Questions.
A paragraph with no other information except that the questioner has searched "everywhere" and found nothing to help them. Here is a classic example:
I have decided to ask this question here after a lot of time spent with Google. I wasn't able to get the answer for my question yet. Here follows the details:
It is irrelevant to the question, and may or may not be true (i.e. you may have missed some information or you may not be aware of some sources). It slows people down while reading your question and it prevents a meaningful snippet from appearing in previews such as in the All Questions list (/questions).
If you are the questioner, then instead of just saying that you've researched, say what you've researched, as well as what you found exactly and how it didn't help.
Don't mark your edits and updates as such. We have the edit history to show what is changed.
I am trying to work out how to sort a list.
Update: I mean an array of integers.
I am trying to work out how to sort an array of integers.