Can other people open localhost?
No. Their localhost points to their computer, not yours.
// works on your laptop. now let's make it work everywhere.
Open it and your browser talks back to your own machine.
127.0.0.1 means “this computer.”localhost = 127.0.0.1
localhost:3000 — famous on your laptop, invisible everywhere else.
A port tells your computer which local app should answer.
:3000 or :5173.localhost:3000 means “this computer, app at door 3000.”No. Their localhost points to their computer, not yours.
Only when you want a public link. Hosting puts your files or app on an internet-connected server.
Publish static files with a static host. If your project needs a server or database, choose an app host.