Multiple sclerosis (MS) can be difficult to understand, not to mention define. In the medical world, MS is often described as “an autoimmune disease that affects the central nervous system.” The disease is caused by the breakdown of myelin, leading to damaged nerves and the formation of scar tissue.

If you’re struggling to grasp this definition, you’re not alone. Here’s how four people with MS describe their condition in layman’s terms.

Year diagnosed: 2009 | Windsor, California

“Terrifying.” That’s how Meagan Freeman describes MS. A nurse practitioner, wife, and mother of six, being diagnosed with the disease certainly wasn’t part of her life plan.

Even as a health professional, Freeman finds that it’s hard to explain MS.

“Those who haven’t met anyone with MS before typically respond with confusion, and ask questions such as ‘What is that?,’” she says. “I usually try to give a simple explanation, something like: ‘My immune system has mistaken my brain and spinal cord for the enemy and tries to attack the coating of my nerves inappropriately.’”

She also explains how it affects her everyday life.

“MS causes extreme fatigue and pain, and this makes parenting especially tough,” Freeman says. “Kids don’t often understand why I am not able to participate in every activity, and it is difficult to explain to friends and family.”

Because she’ll never be able to escape MS, she finds that educating others is helpful. Freeman talks and educates others through her blog, Motherhood and Multiple Sclerosis.

“There are 2 million others in the world going through exactly your experience, and I have never found a more supportive and understanding group of people as I have with the MS community worldwide,” she says.

Year diagnosed: 2013 | Lebanon, New Hampshire

Eleanor Bryan says MS is a “disease that causes you to get on your own nerves.”

She finds that using an analogy can help explain MS: “Our nervous system is similar to a telecommunications system with cords that cover the wires much like a cell phone cable. The substance that covers the cables is a fatty substance called myelin. In MS, the myelin breaks down for an unknown reason. The nerves that are affected have effects like power problems with cables.”

Although her nerves have responded well to medication, not knowing what’s next is the hardest part of living with MS.

“It’s hard to predict how much or when MS will affect you,” she says. “It’s like getting a phone cord you need for life then running it over with a chair accidentally. You still need the cord but you have to use it with care.”

But rather than dwelling on her situation, Bryan finds that taking it one day at a time makes it more manageable. She also started a mini bucket list for things she wants to do, everything from trying out yoga to snorkeling in a wet suit.

“Knowing that I might not have all of the same abilities for years makes me want to take advantage of what I have right now,” she says. “I feel like I live much more in the moment now.”

Year diagnosed: 1998 | Georgetown, Kentucky

“When describing MS to others, I tell them that although things look fine on the outside, inside it’s like a train wreck,” Gary Pruitt says.

He compares the disease to what happens when an electrical system short circuits: “The nerve is like an electrical cord, with the myelin covering the nerve acting as an insulator for the signal sent from the brain to the nerve ending. Much like when the covering is no longer on the electric cord, myelin is lost and the inner part of the cord touches and creates a short in the circuit. The nerves touch each other and short out.”

For his own diagnosis, his doctor and neurologist first thought he had a pinched nerve or a brain tumor. Six neurologists and more than 25 years later, it was confirmed that Pruitt had MS.

While finally finding out that he had MS was a relief, the most frustrating part of it today is that he has to rely on others, mainly his wife.

“I’ve always been very independent, and I’ve had to overcome my resistance to asking for help,” Pruitt says.

While daily chores are a challenge, moving around is easier thanks to his Segway. This motorized device allows Pruitt to stay in control. From running daily errands to traveling, Pruitt and his wife are now able to do things together.

Year diagnosed: 2014 | Charlotte, North Carolina

“Most people either think you are getting ready to die or you’re very sick,” Julie Loven says.

This lack of understanding is something that can be annoying, but Loven sees it as just another bump in the road of living with MS.

“I could get super scientific and describe demyelination but most people don’t have the attention span for that,” she says. “Because MS is in the brain, there is a chance for damage in your brain and spinal cord that can cause issues ranging from loss of sensation in your fingers to the complete loss of mobility and control of bodily functions.”

Like others living with MS, Loven regularly deals with burning sensations, memory problems, heat strokes, and fatigue. Despite this, she continues to have a positive outlook and still does the things she loves most like cooking, traveling, reading, and practicing yoga.

“I’m not saying that MS is bubble gum and roses and a big pajama pillow fight,” she says. “Giving up and in to the fear of the disease is not the thing to do.”