The simplest ways to link two computers

You can connect two computers with an Ethernet cable, a USB cable, or Wi-Fi. Which one works depends on what you want to do — transfer files, share an internet connection, or use one computer to control another. Ethernet is fastest for moving large files. USB works for older machines or when you need a direct, straightforward link. Wi-Fi is most convenient but slower than a cable.

The connection itself is usually automatic once the cable is plugged in or the Wi-Fi network is found. Windows and macOS recognize when another computer is attached and set up basic file sharing without you doing anything. If you need more control — like sharing a printer or accessing one computer's screen from another — you'll need to turn on specific features in your settings.

Key Takeaways

  • Ethernet cables are the fastest option for connecting two computers and work with any machine that has an Ethernet port.
  • USB cables can connect two computers directly, but only work for file transfer and require the right cable type for your machines.
  • Wi-Fi is the easiest method if both computers support it, though it is slower than wired connections.
  • Once connected, you can share files, printers, or internet by turning on sharing features in your operating system settings.
  • Direct connections between two computers work without a router, but connecting to a shared network usually requires one.

Connecting with an Ethernet cable

An Ethernet cable is a thick cord with rectangular connectors on each end. If both computers have an Ethernet port (a rectangular slot on the back or side), you can plug one end into each machine. The connection is when ready — no setup needed. Windows and macOS will recognize the other computer within seconds.

This method is fastest for moving files between machines. A modern Ethernet cable can move data at 1 gigabit per second or faster, which means a 10 gigabyte file transfers in about 10 seconds. The same file over Wi-Fi might take 2 to 3 minutes. Ethernet also works reliably in places where Wi-Fi is weak or unavailable.

The downside is that most laptops no longer have Ethernet ports. If your computer doesn't have one, you can buy a USB-to-Ethernet adapter for $15 to $30. Plug it into a USB port, then plug the Ethernet cable into the adapter. The adapter adds a small delay but still moves data much faster than Wi-Fi.

Connecting with a USB cable

A USB cable can connect two computers directly, but the type of cable matters. Most modern computers use USB-C ports. Older machines use USB-A (the rectangular port) or Micro-USB. You need a cable that matches both computers — for example, USB-C to USB-C, or USB-A to USB-A.

When you plug a USB cable into two computers, one machine usually appears as a removable drive on the other. You can drag files back and forth like you would with a flash drive. This works well for moving a few files or a folder, but it is slower than Ethernet — typically 40 to 100 megabytes per second depending on the USB version.

USB connection is most useful for older computers that don't have Wi-Fi or Ethernet, or when you need a straightforward, no-setup transfer. It does not let you share printers, internet, or access one computer's screen from the other — only file movement.

Connecting over Wi-Fi

If both computers are on the same Wi-Fi network, they can see and share files with each other without any cable. On Windows, open File Explorer, look for "Network" in the left sidebar, and you should see the other computer listed. On a Mac, open Finder, click "Network" at the bottom of the sidebar, and look for the other machine.

Wi-Fi is the most convenient option because you don't need cables and both computers can move around. The downside is speed — Wi-Fi typically moves data at 50 to 150 megabytes per second, depending on your router and how far apart the computers are. A 10 gigabyte file takes 1 to 3 minutes instead of 10 seconds.

For Wi-Fi to work, both computers must be connected to the same router. If one computer is on your home network and another is on a guest network, they won't see each other. Check your router's settings to make sure both machines are on the same network name (SSID).

Sharing files between connected computers

Once two computers are connected by cable or Wi-Fi, you can turn on file sharing to make folders visible to the other machine. On Windows, right-click a folder, select "Properties," then the "Sharing" tab, and click "Share." Choose the other computer's user account from the list. On a Mac, open System Settings, go to "General," then "Sharing," turn on "File Sharing," and add the folders you want to share.

File sharing is different from just seeing the other computer as a drive. When you share a folder, the other user can open it, copy files from it, and sometimes edit files inside it — depending on the permissions you set. You can make a folder read-only (the other person can copy files but not change them) or read-write (they can edit and delete).

If you only want to move files once and don't need ongoing access, you don't need to set up sharing. You can straightforward drag files to the other computer when it appears in your file browser, or email them to yourself.

Sharing a printer between two computers

Once two computers are on the same network, you can print from either one to a shared printer. The printer must be connected to the network — either by Wi-Fi or Ethernet — or plugged into one of the computers with USB.

If the printer is plugged into one computer with USB, turn on printer sharing on that machine. On Windows, go to Settings > Devices > Printers & Scanners, right-click the printer, and select "Printer Properties," then the "Sharing" tab, and check "Share this printer." On a Mac, go to System Settings > General > Sharing, turn on "Printer Sharing," and select the printer.

The other computer will see the shared printer in its printer list and can print to it without the printer being directly connected. This is useful if you have one good printer and want both computers to use it without moving cables around.

Accessing one computer's screen from another

You can view and control one computer from another using remote desktop software. Windows includes Remote Desktop built in — on the computer you want to control, go to Settings > System > Remote Desktop and turn it on. On the other computer, search for "Remote Desktop Connection," enter the first computer's name or IP address, and click Connect.

For Macs, you can use the built-in Screen Sharing feature. On the computer you want to control, go to System Settings > General > Sharing, turn on "Screen Sharing," and note the address shown. On the other Mac, open Finder, click "Network," find the first computer, and double-click it to view its screen.

Remote access is useful if you need to help someone troubleshoot their computer, access files from a distance, or run a program on a more powerful machine. The connection works over your home network or the internet if you set it up correctly, though internet connections are slower.

Sharing an internet connection between two computers

If one computer has internet and the other doesn't, you can share the connection. On Windows, go to Settings > Network & Internet > Mobile Hotspot, turn it on, and the other computer can connect to it like a Wi-Fi network. On a Mac, go to System Settings > General > Sharing, turn on "Internet Sharing," choose which connection to share (Ethernet or Wi-Fi), and select which ports the other computer can connect through.

This is useful if you have a laptop with a cellular connection and want to give internet to a desktop, or if one computer is plugged into a wired connection and you want to share it wirelessly. The computer sharing the connection acts like a router — it slows down slightly because it's handling traffic for both machines, but the difference is usually small.

Frequently Asked Questions

Do I need a router to connect two computers?

No. You can connect two computers directly with an Ethernet cable or USB cable without a router. Wi-Fi requires a router because Wi-Fi is a broadcast signal that a router creates. If you want both computers on the internet at the same time, you need a router or internet-sharing feature.

Why can't I see the other computer on my network?

The most common reason is that file sharing is turned off on one or both machines. Check Settings > Network & Internet > Advanced Sharing Options on Windows, or System Settings > General > Sharing on a Mac, and make sure sharing is enabled. Also check that both computers are on the same Wi-Fi network — guest networks are separate and won't see each other.

What's the fastest way to move a large file between two computers?

An Ethernet cable is fastest, moving data at 1 gigabit per second or more. USB-C is second at 480 megabits per second or higher. Wi-Fi is slowest at 50 to 150 megabits per second. For a 50 gigabyte file, Ethernet takes about 50 seconds, USB-C takes 5 to 10 minutes, and Wi-Fi takes 30 to 60 minutes.

Can I connect more than two computers together?

Yes. If you plug multiple Ethernet cables into a network switch (a small box with many ports), all computers connected to it can see each other and share files. Over Wi-Fi, any number of computers can connect to the same router and network. The more computers sharing the connection, the slower each one becomes.

Is it safe to share files between two computers?

Yes, as long as you control who has access. Set read-only permissions on folders you don't want changed, and don't share folders that contain passwords or sensitive documents unless you trust the other user completely. If the other computer is on a public network or you don't trust it, don't turn on file sharing.