1.

I don't know the limit, but I regularly have two computers logged into my account. My laptop and my desktop, if I happen to have them both on. Having them both on, they recognize it an enable streaming from one machine to the other. However I can only play games on one machine at a time.

It depends on context.

Only one computer can access your Steam library at any given time, so you can't play the same game on 2 computers using your account.

But more computers can be signed into your account through the website. For example... I'm currently typing this on my desktop computer using Opera, but when I grab my phone I'll be able to read my post using Edge because I'm logged on there as well.

Would I grab my laptop I can also read stuff there because that's another device I often use.

All those devices are logged into my Steam account and I don't have to do anything to get access (once in a while I have to log on again, but that's usualy after several weeks).

引用自 8bitbeard：

I don't know the limit, but I regularly have two computers logged into my account. My laptop and my desktop, if I happen to have them both on. Having them both on, they recognize it an enable streaming from one machine to the other. However I can only play games on one machine at a time.

Playing doesn't matter, i'll be playing on one machine anyway at a time using remote play. I just want to know whats the limit

引用自 ShelLuser：

It depends on context.

Only one computer can access your Steam library at any given time, so you can't play the same game on 2 computers using your account.

But more computers can be signed into your account through the website. For example... I'm currently typing this on my desktop computer using Opera, but when I grab my phone I'll be able to read my post using Edge because I'm logged on there as well.

Would I grab my laptop I can also read stuff there because that's another device I often use.

All those devices are logged into my Steam account and I don't have to do anything to get access (once in a while I have to log on again, but that's usualy after several weeks).

As i said above it's only about being logged in at the same time, not playing. I also mean steam clients, this excludes browser & phone

I am unaware of any limit. I've had 4 desktop clients connected at one point, but I've never gone out of my way to push the number higher.

There's nothing in the SSA limiting the number, so give it a shot. Worse case is you get an error and then need to figure out a way to shuffle logins.

I think they changed it recently. I'm all the sudden getting re-sign in requests when i attempt to sign into a 3rd machine, it boots one of the other two off. So I think 2 signed in computers is now the limit. :(
I have a lot of computers that I hop between.

I can understand with games. You wouldn't really be able to play two games at the same time unless you have another person playing and that obviously breaches the terms and conditions set by Steam. However, I have several apps like Blender and game creation software that I like to pipline a workflow through across multiple computers. Streaming is useless because it's only using the GPU/CPU on one computer. The only workaround is to disconnect the internet on the computer running Blender (for instance) and then use Blender on both computers (or whatever software). I guess it would work with offline games too.

As many as you reasonably would use at once from my experience, you can only play games on one though in online mode.
Its so annoying on Origin and Uplay that they always kick me out on the previous PC if I sign in on a second, and have to go through 2FA.