“People are using it to send messages like “Cleaning my apartment” and “Hungry”. You can also add friends via text message, nudge friends, etc. It really a social network around text messaging.”
So mainly updating their social status and locations. Interacting at the social event with #hastags etc.
This evolved into an autistic interaction media stream due to growth and the core function was lost.
This status is now coined by a badge and number of followers and their influence etc.
I'm not a twitter user, but in my view if you want to publish an opinion you might as well to put it in your blog. And when nobody reads it, make a conclusion on whether you should continue that habit or not.
If you want to reach out to people, better use email? Or if you wan to chat with people, use IRC, discord, whatsapp, telegram or something.
Originally? Checking in at places, letting your friends know where you are/what you're doing. From the time before SMS/MMS group messaging was well supported
TechCrunch's article from 2006 on Twittr is interesting: https://techcrunch.com/2006/07/15/is-twttr-interesting/