What Is a Router? How Home and Network Routers Work

Q: What is a router and what does it do?

A router is a networking device that forwards data between different networks, most commonly between your home network and the internet. It decides where to send each packet based on its destination IP address, acting as the traffic director for everything connected to it. In a home it is the central hub linking your devices to your internet connection.

Q: What is the difference between a router and a modem?

A modem connects your home to your internet service provider, converting the ISP signal into data your network can use. A router takes that single connection and shares it among multiple devices while managing the local network. Many ISPs supply one combined gateway box, but they are technically two distinct jobs.

Q: What is the difference between LAN and WAN?

A LAN, or Local Area Network, is the private network inside your home or office where your devices talk to each other and the router. A WAN, or Wide Area Network, is the larger network outside, the internet being the largest. The router sits at the boundary, with a LAN side facing your devices and a WAN side facing your ISP.

Q: What do NAT and DHCP do on a router?

NAT, or Network Address Translation, lets many devices share one public IP address by translating between your devices private internal addresses and the single public address your ISP assigns. DHCP, or Dynamic Host Configuration Protocol, automatically hands out those private addresses to devices as they join the network, so you do not have to configure each one manually.

Q: What is a default gateway?

The default gateway is the address a device sends traffic to when the destination is outside its own local network, and in a home this is almost always the router LAN-side IP address. It is the exit door your packets use to reach the internet. You can find the public IP your gateway presents to the outside world with an IP lookup tool.

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The Traffic Director of Your Network
A router is a networking device that forwards data between different networks, most commonly between your home or local network and the internet. It decides where to send each packet based on its destination IP address, acting as the traffic director for everything connected to it. In a home, the router is the central hub that links all your devices to your single internet connection.
The router is also what presents one public IP address to the world on behalf of your whole network. You can see that public-facing address with our IP Lookup, and the address you reach the router itself on is its default gateway.
Router vs Modem
A modem connects your home to your internet service provider, converting the ISP signal (cable, fiber, or DSL) into data your network can use. A router takes that single connection and shares it among many devices while managing the local network. Many ISPs supply one combined gateway box that does both jobs, but they are technically two distinct functions: the modem gets you online, and the router distributes that connection.
LAN vs WAN
A LAN (Local Area Network) is the private network inside your home or office, where your devices talk to each other and to the router. A WAN (Wide Area Network) is the larger network outside, and the internet is the largest WAN of all. The router sits exactly at the boundary, with a LAN side facing your devices and a WAN side facing your ISP, translating between the two.
NAT and DHCP — Two Jobs Every Home Router Does
NAT (Network Address Translation) lets many devices share one public IP address by translating between your devices private internal addresses and the single public address your ISP assigns. DHCP (Dynamic Host Configuration Protocol) is the service that automatically hands out those private addresses to devices as they join, so you do not have to configure each one by hand. Together they are why dozens of devices at home can share one internet connection seamlessly.
The Default Gateway
The default gateway is the address a device sends traffic to when the destination is outside its own local network. In a home that is almost always the router LAN-side IP address, commonly something like 192.168.1.1, and it is the exit door your packets use to reach the internet. If you need to find yours, see how to find your router IP address.
Frequently Asked Questions
What is a router and what does it do?
A router is a networking device that forwards data between different networks, most commonly between your home network and the internet. It decides where to send each packet based on its destination IP address, acting as the traffic director for everything connected to it. In a home it is the central hub linking your devices to your internet connection.
What is the difference between a router and a modem?
A modem connects your home to your internet service provider, converting the ISP signal into data your network can use. A router takes that single connection and shares it among multiple devices while managing the local network. Many ISPs supply one combined gateway box, but they are technically two distinct jobs.
What is the difference between LAN and WAN?
A LAN, or Local Area Network, is the private network inside your home or office where your devices talk to each other and the router. A WAN, or Wide Area Network, is the larger network outside, the internet being the largest. The router sits at the boundary, with a LAN side facing your devices and a WAN side facing your ISP.
What do NAT and DHCP do on a router?
NAT, or Network Address Translation, lets many devices share one public IP address by translating between your devices private internal addresses and the single public address your ISP assigns. DHCP, or Dynamic Host Configuration Protocol, automatically hands out those private addresses to devices as they join the network, so you do not have to configure each one manually.
What is a default gateway?
The default gateway is the address a device sends traffic to when the destination is outside its own local network, and in a home this is almost always the router LAN-side IP address. It is the exit door your packets use to reach the internet. You can find the public IP your gateway presents to the outside world with an IP lookup tool.
Last updated: April 2026