Here’s a question I often ask when texting that might flummox you as well: When your phone shows those three dots, what exactly does that mean? Is someone always typing away? Or does it mean that they entered text and wandered away? Can you tell the difference?

That series of blinking ellipses on an iPhone can be both a useful tool and a source of stress. The same thing goes with Facebook messenger or whatever other instant messaging service you use. As the “someone’s typing” indicator incessantly glares back at you, you can’t help but think up the most stomach-churning response possible.

So what’s the deal with the guessing game? Aka when someone’s typing are they really typing?

The roots of “someone’s typing”

According to Gizmodo, it all started with Microsoft. When Microsoft’s engineers first decided to add a typing indicator to the Microsoft Messenger Service, it was simply to let you know that the person you were speaking to was still on the line. This was back in the dial-up ages, before emojis existed. So the typing indicator was originally meant to reassure users.

The original Microsoft typing indicator was triggered on the first keystroke and repeated as more keystrokes occurred. If no keystrokes were registered after 10 seconds, the indicator would no longer be displayed. Either you were typing, or you weren’t.

Facebook messenger, Slack and beyond

The messaging and collaboration tool Slack adapted a similar approach: Gizmodo reports that Slack will only let you know that someone is typing as soon as they start typing — but not if they have only clicked in the text box. If a user stops typing for five seconds, Slack removes the “person is typing” indicator. (You can turn off Slack’s typing indicator in Preferences.)

For Apple, it takes five seconds for the bubbles to disappear if you clear the text field — but 60 seconds to disappear if you just stop typing.

As for Facebook messenger, the typing indicator shows up immediately in the Messenger box as soon as a single character is entered. The catch here is that even if that character is a space, the typing indication will pop up (ah yes, my anxiety senses are tingling). Still, the indicator should disappear 5-10 seconds later, as long as no additional characters are entered.

Finally, we have Apple’s iMessages. Essentially, you’ll see the ellipses bubble as soon as characters or spaces are entered and it’ll take five seconds to disappear if you clear the text field — but 60 seconds to disappear if you just stop typing. Oh and if you load a picture without sending it, the triple dot bubble may just chill there indefinitely.

Thanks a lot, Apple.

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