Of course you may have an idea about the likely meaning of this specific event, in the light of the literal meaning of the word “poke”—“to push your finger or something thin or pointed into or at someone or something” (Merriam-Webster). But to dispel any doubts, an investigation is needed. Thus I googled for answers.. and found hundreds and hundreds of questions and answers.
First of all, what I learned from my search is that a very beloved feature—a button called “Poke”—was enabled since the day Facebook launched in 2004. The button didn’t come with any explanation or rules. Mark Zuckerberg, then 23, said he just wanted to make something with no real purpose..
Secondly, I learned that the Facebook poke was once considered to be a creepy flirting tool, but now it has evolved into something very different. In fact, the most common answer is that a poke on Facebook is more or less the equivalent of tapping someone on the shoulder to say a quick “hello.”
Another popular interpretation is that it is a way to let other people know that you are thinking of them without going through all the trouble of sending private messages or posting publicly to their online wall. A very simple and kind way of saying things like “Remember that I’m here if you’re in troubles, if you feel worn out, or if you need anything,” or just “I miss you,” or “I want you to know that I care about you and what you're going through.” Interesting, isn’t it? Well, of course you might say, “Wouldn’t it be better to just pick up the phone and call her/him?” To which one could reply, “Yes, but sometimes (not to say always) life is more complicated than we would like!” A very strong counter argument, in my view.
Thus, Facebook makes it easier to express our inner feelings and thoughts. Which is not a small thing, above all in these harsh and troubled times.
That being said, however, it is clear that you shouldn’t poke people you don’t really know, especially because you can’t always predict the consequences, if you understand what I mean.., and certainly you shouldn’t take a poke too seriously—remember that 99 times out of 100 a poke is meant to be just for fun.
In any case, and to conclude, I’d say that the main result of my investigations on this subject may be stated as follows: there are no rules for this kind of thing—instinct, common sense, and good taste should guide us here. My viewpoint, for what it’s worth, can perhaps best be summed up by the cartoon below.. ;)
Keep up the good poking!