Real time text chat is a useful thing. Especially for work. To make effective use of this communication tool, one must learn and understand basic etiquette and norms.
You probably got sent a link to this page by a chat administrator or your colleague, who is tired of the way you use a chat at work. This page should teach you how to avoid being put in this situation again.
Mind your grammar. All modern operating systems offer spell check - use it. You will not be taken seriously if you can't spell or structure a basic sentence. It's that obvious.
Keep is simple. Write a short and clear message. As a rule of thumb, anything over 512 symbols should be an e-mail.
Mention the recipient. If you are addressing someone directly, mention them so they get a notification and a highlight which indicates one needs their attention regarding a specific subject.
Search before asking. The vast majority of questions can be answered by Google or another search engine. Take the twenty seconds to search. Also searching the chat history might be useful, if all fails, ask.
Never stack-post. Simply don't do it. Write one message and wait for the recipient to read it. Edit if required. Do not send a pile of single sentence messages, this is very obnoxious to read and reply to for the correspondent.
Don't leave people on read. If someone sent you something in a private chat, reply. There is no "but", you need to reply. The reply could be as basic as a simple "OK" as long as you indicate that you read and understood the message. Even though most IM standards have a way to show if your message was read, this is being polite.
Don't ask to ask. What infuriates me is when someone writes something along the lines of "Hello, can I ask a question?" In a chat. This is pointless and there are plenty of pages on the web aimed at people who do it, but I will demonstrate anyway:
User1: @User2 hey, can I ask you something?
User2: hey, what is it?
*** User 2 is waiting for User1 to write the question. ***
User1: I am having an issue with Grafana, do you know how to [do this]
User2: yeah, you have to [solution]
As you can see, User2 had to wait, let's try that again:
User1: Hi @User2, I have an issue with grafana, do you know how to [this]?
User2: Hello, yes, you need to [solution]
Don't mention people unless you have to. Nobody wants to get notifications for no reason, what will end up happening is everyone will not pay attention to your mentions or will set you as "ignored".
This is mostly targeted at XMPP, Slack and IRC users, since we use IRC a lot, but this also applies to other IM tools such as Matrix, TOX, Microsoft Teams, Telegram and others.
I absolutely hate email. Especially replying to them for business reasons.