Now, with texting and online chats, things have changed. The full stop decided it wanted more power. It still ends things, but now it does so in a more literal sense; the full stop is brutal in its finality. It can be inferred as being angry or rude.
The difference between “I’m fine” and “I’m fine.” is just a small little dot, but that dot subtly changes the idea. It’s not longer a casual indication of your well being. It adds a hidden meaning. It’s saying you’re not fine at all but don’t want to explicitly state it.
In terms of body language, I’d say it’s like folding your arms and frowning while conversing with someone, speaking in short abrupt sentences and not making eye contact.
Personally, I find that I don’t use the full stop very much in online chats/texts. I simply put separate sentences and independent thoughts/ideas on different lines. Even with text messages, I’d rather send 3 stand-alone texts than shove all 3 ideas into one complicated paragraph of text.
It maintains an organisational structure to my thoughts and other people find it a lot easier to comprehend what I’m going on about. Bitesize pieces of information are easier to digest than a mountain of text.
Also, it makes the chat seem friendlier and more welcoming, like an actual conversation and not just a collection of sentences.
Punctuation speaks louder than words.