Do you have a favorite?

I want to use something that is simple and will not bring me a lot of SPAM in my mailbox. An it has to be free, of course.

I have Google HANGOUTS, but I don not use it MUCH. For one thing, I hate the name 'hangouts'.  That is so juvenile.

Here is a list of the old ones:
https://www.lifewire.com/once-popular-old-instant-messaging-services-3486135

Any recommendations?
I have been using Pidgin for years. No complaints.

https://en.wikipedia.org/wiki/Pidgin_(software)For me, Facebook Messenger does the job.
On the iPhones, and iPad, it has a seperate app so i don't need to touch that Facebook stuff.Mark,
Please explain how to use the Facebook messenger.
Facebook drives me crazy.
I have a hard time understanding what it is doing. 
geek,
I'm with you on the Facebook front, don't get it myself, but each to his own.

As to usage, two OPTIONS, get the app from your favourite App Store, or click the Messenger icon in Facebook.

Then it's just like any IM app, you type your stuff and the other party responds.

One advantage is you can set up Groups where you can just send to particular people.

I THINK you'll find it PRETTY straight forward to pick up.