Can someone explain what Postman or Bruno is for? I know it's something for interacting with apis but why would i use it. I interact with apis a lot with curl or wrapper in my languages but never really needed something else?
1. Easier to organize collections of requests in a visual hierarchy
2. Environments mean you can use the same collection to easily execute against local, dev, staging, production, etc.
3. Pre- and post-execution scripts mean you can programmatically extract values and chain into other requests (think grabbing an access token from an oauth request then using that token for an authenticated request)
It's basically just convenience features, nothing you can't get with other tools.
Of course you could also just check in to version control these requests as curl commands, so if your team has the technical knowhow, that's about almost the same.
Or even better, you write some tests in your language to make these requests, then you have an integration test, too.
Sometimes, you have to find out how an API works, exactly. Sometimes you want to test your own APIs in ways the regular clients do not allow.
We have multiple environments with multiple parallel versions (think like dev/staging/prod and current/legacy), these deployments mostly have the same API with slightly different urls and credentials
We use multiple environments to easily switch between the various versions both for one-off operations (like a clear cache call that only needs to be called few times a year in response to external actions) and to manually test features.
I can see why not everybody would have this use case
Iirc Bruno does not have enough environment/variables/pre-post-request scripting support
If you're really comfortable with all those tools, you won't understand Postman because you'll say "why don't people just chain all these tools together?". It's like the famous hn comment on dropbox, "why don't people just use rsync"?
It's technically true, and if you're adept at those tools, you should probably use them instead of Postman. But yea, it's a useful product for a bigger set of people.