Chances are you were sent here by someone within Slack, IRC, or another chat after you've started the conversation just saying "Hello" or "Good Morning!" waiting for a response, and now you're curious what they tried to tell you with this link…
Well, yes and no:
While it is polite to start a chat with an introduction, when you just say "Hello" and then wait for a response, you force your chat partner to either ignore your introduction or respond to it wondering why you've started the chat in the first place. This creates unnecessary delays and interrupts their workflow.
Let's imagine Debbie and John. Debbie is working on something difficult and is highly concentrated on that task while John needs to ask Debbie a question:
In this example, Debbie received John's chat, stopped working on the task she was working on, and asked him how she can help. After she had done so, John starts to type his question and Debbie either tries to get back to her task or waits for him to complete typing his question as she's seen the typing indicator. Either case causes her to lose her focus on her work at least once, and it will probably take her some time to get back to it.
Now let's take a look at a better example:
Here some things went better than in the example above:
You're trying to be polite by not jumping right into the request, like you would do in person or on the phone. But chat is neither of those things. Typing is much slower than talking. Instead of being polite, you are just making the other person wait for you to phrase your question, which is lost productivity.
The same goes for "Hello -- Are you there?", "Hi -- quick question.", "Do you have a sec?", "yt?" and "ping". Just ask the question!
If you feel it's too brusque to simply say "Hi" and ask the question, you can do something like this:
Additionally, asking your question before getting a reply allows asynchronous communication. If the other party is away, and you leave before they come back, they can still answer your question, instead of just staring at a "Hello" and wondering what they missed.