What Is Hosting?
Where your app actually runs once it leaves your laptop, and how to choose a host

Sprout presents
Your app currently lives at localhost, an address precisely one computer can reach. Hosting raises that number to everyone, which I find thrilling.Your app currently lives at localhost, an address precisely one computer can reach. Hosting raises that number to everyone, which I find thrilling.

Right now your app probably runs on exactly one computer... yours. Hosting is how it moves to a computer that's always on, always connected, and reachable by anybody who has the address. This lesson covers what a host does, where it sits in your app, and what to look for when you pick one.
The Problem Hosting Solves#
When you run an app on your laptop, it lives at an address like http://localhost:3000. That address only works on your machine. Close the lid, lose Wi-Fi, or shut the computer down, and poof, the app is gone.
Real users need three things your laptop just can't give them.
- An address that works anywhere, like
myapp.com - A computer that never sleeps, so the app is still up at 3am
- Room to grow, so a few extra visitors don't knock it over
A hosting service gives you all three. It runs your code on computers in a data center and hooks them up to the internet for you.
Where Hosting Sits in Your App#
Think back to frontend and backend. Every app has a part people see and a part doing the work behind the curtain. Both of them have to run SOMEWHERE.
Visitor's browser
|
v
Your domain (myapp.com)
|
v
+-------------------+
| HOST |
| frontend pages |
| backend code |
+-------------------+
|
v
Other services (database, email, payments)The host is home base. Visitors show up there, and the code running on your host talks to all the other services you'll meet over the next few modules.
What a Host Does for You#
Step 1. Takes Your Code#
Most modern hosts connect to your GitHub repository. When you push new code, the host notices.
Step 2. Builds It#
The host runs the same build command you'd run yourself, such as npm run build, and turns your code into something ready to serve.
Step 3. Runs It#
The host starts your app on its computers and keeps it running. If it crashes, a lot of hosts will restart it for you.
Step 4. Gives It an Address#
You get a web address right away, and you can hook up your own domain name later.
Step 5. Keeps It Healthy#
Hosts show you logs, so you can see what your app is up to, and they let you roll back to an earlier version when a new one breaks.
That whole trip, from push to live site, is called a deployment. You'll do a bunch of them in this module.
Two Styles of Hosting#
Hosts come in a few shapes. The two you'll meet here show the main split.
| Style | What It Means | Good For |
|---|---|---|
| Always-on server | Your app runs continuously on a server you rent | Backends, APIs, background jobs, apps with a database next to them |
| Frontend and serverless | Pages are served from a global network, and backend code runs only when a request arrives | Websites and Next.js apps, especially ones with lots of pages |
Is one style better? Honestly it depends on the app, and plenty of projects use one of each. Our own stuff is a good example. Seedly Sites deploys to Cloudflare Pages, while Seedly CRM is source code the owner deploys on infrastructure they control. Different jobs, different homes.
What to Look For in a Host#

When you're comparing hosts, run through these questions.
- Does it deploy from GitHub? Push to deploy saves you a TON of manual work.
- Does it support your kind of app? A Next.js site, a Node.js server and a Python script all have different needs.
- Can it run a database next to your app? Some hosts can, and some expect you to use a separate service.
- How does it handle secrets? You need a safe spot for API keys, called environment variables.
- Can you connect your own domain? And does it give you HTTPS for free?
- Can you see logs and roll back? You'll want both the very first time something breaks (and something always breaks).
- How does pricing work? Some charge for the time your app runs, others for requests or bandwidth.
The Hosts in This Module#
This module covers two popular hosts, one from each style.
| Host | Style | Known For |
|---|---|---|
| Railway | Always-on server | Running full apps and databases together with little setup |
| Vercel | Frontend and serverless | Hosting Next.js sites, made by the team behind Next.js |
Each one gets its own chapter. You'll set up an account, deploy an app, add environment variables, connect a custom domain and more. By the end you'll know which one fits which job.
TL;DR#
- Hosting runs your app on computers that are always on and reachable from anywhere
- A host takes your code, builds it, runs it and gives it an address
- Pushing new code and having it go live is called a deployment
- Always-on servers and frontend or serverless platforms are the two main styles
- Compare hosts on GitHub deploys, app support, secrets, domains, logs and pricing
- This module covers Railway and Vercel
What's Next?#
Up next is the Railway chapter. You'll find out what Railway is, make an account, and put your very first app on the internet...
This lesson ends with 2 short activities.
