What is a Modem? A Beginner's Guide For Those Not Into Tech

Does contacting tech support feel a bit overwhelming? Does the technical jargon you're expected to know give you a small headache?

We've all been there, so there's no shame in being confused. But it might help if tech support was a bit less technical.

With this article, you won't have to go through a 40-minute phone conversation just to learn the basics. If you want to know about modems, equipment, and other technical terms in the industry, keep reading!

What is a Modem?

A modem connects you to the internet through a physical connection. This physical connection is through a wire that leads outside. Eventually, it reaches your Internet Service Provider (or ISP).

Your ISP gives you access to the world wide web through that physical connection. A modem is defined by its connection to the internet, not to other computers.

That means if a modem doesn't have a connection to the internet, it isn't a modem. It’s the only device that can give you internet access.

Some technical staff might refer to the internet as a WAN (Wide Area Network). This means it's a bunch of computers covering a wide area. The internet covers the widest area: the entire world.

Modems don't automatically come with advanced features like Wi-Fi. Pure modems only do one thing: connect you to the internet. Below, you'll get a basic understanding of how that connection works.

How Does a Modem Work?

A modem works by translating digital data into electric signals. The signal is then transformed back into digital data so your computer can use it.

In fancy terms, a modem stands for “modulator-demodulator,” which is confusing. We've broken these technical terms down for you below:

A modem “modulates” when it takes the digital data you know and turns it into an electric signal. This way, that electric signal can travel along wires.

The modem then “demodulates” when turning that electric signal into digital data so your computer can use it.

This happens anytime you send an email, open a web page, or play an online game. It also occurs anytime you watch a funny cat video, which looks something like this:

1. You click the play button (this sends a request to watch the video)
2. The website receives the signal and sends the video (the digital data you want)
3. The cat video is “modulated” into an electric signal to be sent.
4. When it reaches your modem, it's “demodulated” into its original form (back to the cat video)

Other electronic communication devices follow this rule as well. For example, your telephone transforms your voice into electrical pulses that travel through wires and then is translated back into your voice on the other end.

Electric wires can only handle transporting electric currents. If they could handle other kinds of data, like sound, you could shout into a nearby outlet to talk to someone in another room.

The Four Different Types of Modems

Different modem types handle translating data to electricity in different ways. There are four different types of modems based on speed and connection type.

• Dial-up Modem uses your phone line to connect. Using a dial-up connection means you can't make calls when using the internet unless you have multiple phone lines. You must get off the phone to use the internet (and vice versa). Because dial-up is slow and inconvenient, and internet technology has improved drastically over the last few decades, it's pretty much phased out in most areas.
• DSL Modems also use your phone line to connect, but with more speed potential. DSL connects with ethernet cables (the most common internet cable). You’ll need a splitter to connect your phone and internet into one port, but you can talk and surf at the same time. This modem is faster than dial-up but slower than other connection types.
• A Cable Modem uses your cable line to connect. Cable connections are designed to send video, which is a more complex signal. Therefore, cable internet is faster than both DSL and dial-up. You can also watch TV while using the internet without needing a splitter. Cable internet is incredibly popular in the United States.
• Fiber Modems rely on specialized fiber-optic cables to connect. Fiber connections offer the fastest internet in the world. However, fiber isn't available everywhere. It's the only internet type that doesn't rely on existing cables, meaning you need them to be installed, usually by the ISP company. It is most popular in large population areas, where the cost to install a fiber network is spread across more people. Fiber-optic lines use pulses of light that travel across the cables near the speed of light, making it the fastest connection by far.

What Internet Speed is Right for Me?

The modem you buy depends on what you use the internet for. Are you streaming Netflix shows, gaming with friends, and video conferencing into work or just checking email and shopping for new shoes?  Video streaming takes up the most bandwidth in a household while checking emails takes the least.

Bandwidth refers to the speed potential of your internet. Fiber offers the best bandwidth, while dial-up offers the weakest.

If we think of bandwidth like a garden hose, your dial-up, DSL, and cable modems all have water pressure and decent flow. However, fiber is like a pressure washer, able to quickly move high volumes of water (data).

Buying fiber internet when you only check your email is like purchasing a pressure washer to water your plants. It’ll do the job, but it’s a little overkill.  Fiber internet is better for larger families watching movies and playing online games.

Remember this the next time an ISP tries to sell you on a premium internet package.

Difference Between Internet Equipment: Modem vs. Router vs. Gateway

The definitions of internet equipment might seem like they are interchangeable but there are huge differences between the three most common pieces of gear: modems, routers, and gateways.

We defined the modem above as the equipment that physically connects you to the internet but there are other components to a home internet network. Here, you'll find out how you can be sure you are getting the right pieces of equipment that best serves your household needs. Read more in our article on What is the Difference Between a Modem and a Router?

What is a Router?

Routers let you connect all of your household internet devices to one point. You can think of a router as an advanced version of your ethernet cable splitter. However, routers typically support over four computers while a splitter only supports two.  A router is needed to connect all your devices at home to the internet wirelessly through Wi-Fi.

While modems connect you to the biggest WAN (the internet), routers create a LAN (Local Area Network). The LAN includes all the computers in your local network, usually your home.

Routers connect you to your LAN, but if that LAN connects to a modem, all the computers on your LAN can connect to the WAN (internet). You don't need a router to connect to the internet.  Remember, that is the modem’s function.

LANs let you send files between computers without needing to use the internet. For example, if you use Microsoft's operating system (Windows), you can use the computer's sharing settings to share files to any other device on the LAN.

Routers also have the distinct advantage of providing an extra layer of security. They have built-in firewalls blocking unwanted connections, a feature unavailable in cable splitters or pure modems. Your computer also has a built-in firewall, but some extra protection never hurt.

To be sure you are getting a router (not a modem), ask if the router can connect to the internet by itself. If it needs a modem to connect to the internet, you have a pure router.

To read more in-depth information about routers, visit our full article on What is a Router?

What is a Gateway?

A gateway is a combination of a router and a modem. So, a gateway can connect you to the internet and provide computers with a local connection.

Gateways are the most convenient option when shopping for internet equipment. Being able to rely on one box instead of two is pretty helpful.

Gateways will almost always connect to the internet. But, some tech support personnel use “gateway” to refer to modems.

If you want to be sure your gateway is a router-modem combo, ask if it supports local and internet connections. You can also ask if it has router-specific features, like wireless internet.

Internet Equipment Terminology You Will Likely Come Across

Regarding internet terminology, you might hear about other pieces of equipment. If you speak to an ISP sales rep, they might forget to explain what that equipment does, prioritizing the sale.

This is why it's so important to be armed with knowledge beforehand. Here's a breakdown of different pieces of equipment you might hear about:

• Hub – a “network hub” connects multiple computers or devices with a single access point. Hubs are largely unused in home networking because they lack the security and sophistication of routers. However, you might hear the term used interchangeably with router, gateway, or switch.
• ONT – stands for Optical Network T This is the fiber-optic equivalent of a modem, so you need it to connect to the internet on a fiber network.
• Wi-Fi extender – a device that extends the range of your wireless network. If your computer has a weak wireless connection, an extender can help that connection reach farther. These tools are handy in larger homes.
• Mesh Wi-Fi router – a specialized wireless router with one “main router” and multiple network extenders. Mesh systems are handy if you use numerous Wi-Fi extenders and have network stability issues. These routers are great if you rely on multiple extenders.
• Ethernet cables – the basic cables used to connect your computer to the router. Network technicians might call these “RJ45” cables. This is the most popular cable for LAN and DSL connections.
• Fiber-optic cables – the advanced cables necessary to connect fiber optic networks. These cables reflect light, which is faster than the electricity that goes through basic cables. This light reflection is what gives fiber-optic internet its speed.
• Coaxial cables – these cables are necessary to connect via cable internet. They are identical to what you use to connect a television box.
• Switch – a massive router-like contraption used to send and sort data within LANs. You might see these in large offices and data centers. Home networks don't often require these.
• Bridge – a device that connects to separate LAN networks as though they are one. Because they are used to extend large LAN networks, you won't likely need one for your home.
• Repeater – an internet device that increases the range of a physical internet connection. As cables get too long, they lose some signal power. Repeaters can reignite this power in cable networks. You won't need these unless your home is very large and wired.

Switches, bridges, and repeaters aren't commonly used in homes, so you are less likely to hear about them.

Other terms (like mesh systems) are buzzwords ISPs use to sell impressive-sounding products. Knowing the terms helps you better understand what you need.

It's also good to know that you need different cables depending on your network. That way, you won't need to return equipment to the store.

The Pros and Cons of Getting Your Own Modem vs. Getting an ISP's

Internet service providers have no problems tacking on an extra equipment rental fee if you get a modem. You might be tempted to shop for your own modem, router, or gateway as a result. But before you do that, consider this quick list of pros and cons:

Pros & Cons of Purchasing Your Own Modem:

Pros	Cons
No equipment rental fees	High upfront costs (up to $100)
You control what you get	Your equipment might not work with your network
You'll naturally get a better understanding of how to use it	You'll need to spend time learning how to use it

 Pros & Cons of Using the ISP's Modem

Pros	Cons
No high upfront costs	You usually end up paying more
You know the modem works with your network	You might have to pay installation costs
Tech support has easier access to these modems	You might not learn how to fix it yourself

Other Internet Terms You'll Hear When Speaking To Tech Support

Beyond the equipment, there are other terms you need to know when looking for modems. Below, we define those terms so you can better follow any Internet conversation:

• Upload speed – the speed at which you send data from your computer to everywhere else. High upload speeds are useful if you work from home and join video meetings.
• Download speed – the speed at which you receive data from other sources. Incredibly handy for getting files fast, watching high-quality videos, and avoiding internet slowdowns.
• Bandwidth – the volume of data sent over a network. Networks that can handle more bandwidth tend to be faster and more reliable.
• MAC address – one way devices can find you on a network. MAC stands for Media Access C It’s a permanent fixture of each device, like the VIN on your vehicle. MACs are mostly useful for local transfers.
• IP address – another way devices can find you on a network. It stands for Internet Protocol, and unlike MAC addresses, they are always changing. IPs come in two forms: the simple IPv4 (four sets of numbers like 1.0.0.127) and the impossibly long IPv6 (for the internet). You can use your router’s IPv4 address typed into your web browser to manage its settings.
• DNS – a Domain Name System that creates the web addresses, or URLs, that lets you access a web page. For example, Google's domain is “www.google.com.” This is an alternative to typing in the site's IPv6 address, which is impossible to remember.
• Access point – a fancy way to refer to where you access the internet (like your modem or gateway).
• VPN – a Virtual Private Network creates a secure tunnel you can use to obscure your connection data. You might hear it as an internet security option, but it doesn't do anything about viruses. You need antivirus software (like Windows Defender, which comes with Windows 11) for that.
• Wi-Fi – stands for Wireless Fidelity, and it is the name of the organization that created wireless connections. People use “Wi-Fi network” to refer to any wireless connections.
• WPA – stands for Wi-Fi Protected A It is a built-in security protocol in many routers. You won't find WPA security in modems, but you will find them in gateways. WPA keys (also called WPA2 and 3 to indicate more advanced security) are located on the side of your router.
• WPS – stands for Wi-Fi Protected S It lets you allow your house guests to access the wireless network (but without giving them the password).

Wrap Up

What makes a modem a modem? To make a long story short: it's a device that physically connects to the internet. If it doesn't do that, it isn't a modem.

Modems work by translating digital data into electric energy. But the latest technology (fiber) doesn't need to transform data into electricity anymore.

If you want to use this article for your next tech support conversation, bookmark it! Then, you can use it to bolster your knowledge. If you’re lucky, you might even impress the customer service agent!