What's the Difference Between Mold and Mildew?

iStock.com/AndreasReh
iStock.com/AndreasReh

We’re all familiar with colorful spots of something growing in our showers and in other dark, damp areas in our homes, but you may not know what to call it. Is it mold, or is it mildew? What is the difference between the two, anyway?

Both terms refer to fungus, but as it happens, it’s a squares-versus-rectangles situation. Mildew is a type of mold. The term typically describes fungi that grows flat, on surfaces like the walls of your shower or window sills. There are also several types of mildew that are specific to plants—powdery mildew and downy mildew are parasites that grow on certain trees, flowers, and crops, for example. While mold might be a colorful green or black, mildew is typically white.

The word mildew originally came from honeydew, a term for sticky secretions aphids and other insects leave on plants, which people used to think came from the sky, like dew. Eventually, the word came to refer to the mold caused by the fungi that fed on these secretions.

Leaves covered in white powder
Powdery mildew on maple leaves
iStock.com/kazakovmaksim

Most of the household growths we refer to as mold belong to just a few families of fungi species. According to the CDC, the most common indoor molds are Cladosporium, Penicillium, Aspergillus, and Alternaria. Household molds can be a variety of colors, from orange-brown to green to gray to black. (Note that not all mold that is black in color is the more toxic species we call “black mold,” or Stachybotrys.) In contrast to the powdery texture of mildew, molds are typically fuzzy or slimy.

In nature, mold can play an important role in the ecosystem, breaking down dead plants and leaves. In your house, those decomposition abilities aren’t quite so welcome. Mold spores fly through the air, and when they land in moist places, they start to grow—whether that’s on food, your ceiling, paper products, wood, carpet, leather, or elsewhere around your house—and in the process, destroy whatever they're growing on. Unlike mildew, most molds grow down into the surface of its habitat, making them more difficult to remove. In porous materials, mold grows into all the empty crevices, which is why it is often impossible to remove all the mold from ceiling tiles (or soft foods like bread).

Mold growing under a windowsill and near the carpet of a home
Mold growing in a Nashville home following a flood
Martin Grube, FEMA // Public Domain

Getting rid of the unsightly growth in your damp bathroom is more than just a matter of aesthetics. Indoor mold can cause allergic reactions, such as a stuffy nose or itchy eyes, and can lead to infections for people with compromised immune systems. Some people are more sensitive to mold than others, and may experience more symptoms when exposed to it. Generally speaking, though, mold spores are everywhere, so you’re never going to live a totally mold-free life. Spores will come into your home through windows, doorways, ventilation and climate control systems, and via your clothing, shoes, and pets.

But there’s only one way to effectively inhibit mold growth at home: Get rid of the moisture. That means fixing leaks, getting better ventilation, and possibly running a dehumidifier, according to the CDC’s recommendations on mold.

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7 Massage Guns That Are on Sale Right Now

Jawku/Actigun
Jawku/Actigun

Outdoor exercise is a big focus leading into summer, but as you begin to really tone and strengthen your muscles, you might notice some tough knots and soreness that you just can’t kick. Enter the post-workout massage gun—these bad boys are like having a deep-tissue masseuse by your side whenever you want. If you're looking to pick one up for yourself, check out these brands while they’re on sale.

1. Actigun 2.0: Percussion Massager (Black); $128 (57 percent off)

Actigun massage gun.
Actigun

Don't assume you need a professional masseur to provide relief—this massage gun offers 20 variable speeds and can adjust the output power on its own according to pressure. Can your human massage therapist do that?

Buy it: Mental Floss Shop

2. JAWKU Muscle Blaster V2 Cordless Percussion Massage Gun; $260 (13 percent off)

Jawku massaging gun.
Jawku

This cordless, five-speed massager uses a design that's aimed to increase blood flow, release stored lactic acid, and relieve sore muscles through various vibrations.

Buy it: Mental Floss Shop

3. DEEP4s: Percussive Therapy Massage Gun for Athletes; $230 (23 percent off)

Re-Athlete massage gun.
Re-Athlete

Instant relief is an option with this massage tool, featuring five different attachments made to tackle any muscle group. You can squeeze in eight hours of massage time before you have to charge it again.

Buy it: Mental Floss Shop

4. Handheld Massage Gun for Deep Tissue Percussion; $75 (15 percent off)

Massage gun from Stackcommerce.
Stackcommerce

With five replaceable heads and six speed settings, this massage gun can easily adapt to the location and intensity of your soreness. And since it lasts up to three hours per charge, you won't have to worry about constantly plugging it in.

Buy it: Mental Floss Shop

5. The Backmate Power Massager; $120 (19 percent off)

Backmate massage gun.
Backmate

Speed is the name of the game here. The Backmate Power Massager is designed for fast, effective relief through its ergonomic design. Fast doesn’t need to mean short, either. After the instant relief, you can stimulate and distract your nervous system for lasting pain relief.

Buy it: Mental Floss Shop

6. ZTECH Percussion Massage Gun (Red); $80 (46 percent off)

ZTech massage gun.
ZTech

This massage gun looks a lot like a power drill, and, similarly, you can adjust its design for the perfect fit with six interchangeable heads that target different muscle areas.

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7. Aduro Sport Elite Recovery Massage Gun (Maroon); $80 (60 percent off)

Aduro massage gun.
Aduro

Tackle large muscle groups, the neck, Achilles tendon, joints, and small muscle areas with this single massage gun. Four massage heads and six intensity levels allow this tool to provide a highly customizable experience.

Buy it: Mental Floss Shop

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Do Politicians Need a Musician's Permission to Play One of Their Songs at a Campaign Event?

Dyana Wing So, Unsplash
Dyana Wing So, Unsplash

Whether it’s the songwriter, the performer, or the recording label, someone always owns the rights to a song. Whether or not one needs permission to play that song depends a lot on the circumstances. A DJ at a wedding doesn’t need to worry about any consequences for playing Peter Gabriel's “In Your Eyes” or The Righteous Brothers's “Unchained Melody.” Sports arenas can pipe in the Rolling Stones's “Start Me Up” without a release.

In the world of politics, however, campaigns and rallies that rely on music to stir up crowds often come under fire for unauthorized use. What’s the reason?

According to Rolling Stone, it’s not typically an issue over copyright, though using a song without permission is technically copyright infringement. If a song is played in a public venue like a stadium or arena that has a public performance license, no permission is needed. The license is typically granted through a songwriters’ association like the American Society of Composers, Authors, and Publishers (ASCAP) or Broadcast Music, Inc. (BMI). Even so, ASCAP still recommends [PDF] that political campaigns seek out permission from the musicians or songwriters, as these licenses exclude music played during conventions or campaign events.

Additionally, most artists aren’t concerned with their music being played at a wedding or sporting event. It is, after all, a form of free publicity and exposure, and no one is really making any substantial amount of money from their work. But the political realm is different. Because artists might have differing political beliefs than a candidate using their music, they sometimes grow concerned that use of their material might be construed as an endorsement.

That’s when artists can begin to make noise about wanting politicians to stop playing their music. In this instance, they can object on the basis of their Right of Publicity—a legal argument that covers how their image is portrayed. They can make the assertion that use of their work infringes on their right to not be associated with a subject they find objectionable. Other arguments can be raised through the Lanham Act, which covers trademark confusion (or a False Endorsement), which addresses the implication an artist is endorsing a political message if their music is used.

In 2008, for example, Jackson Browne won a lawsuit against John McCain and the national and Ohio GOP when the McCain campaign used Browne’s song “Running on Empty” in ads attacking Barack Obama over gas conservation.

Even if the musician isn’t supportive of a candidate, it’s not always advisable to take such action. A contentious legal confrontation can often result in more publicity than if a musician simply let the campaign continue uninterrupted. Other times, recording artists feel strongly enough about distancing themselves from a message they disagree with that they’ll take whatever steps are necessary.

The bottom line? More often than not, a song played during a campaign isn’t there because an artist or label gave their permission. And unless the artist strenuously objects to the campaign message and is willing to get into a legal tussle, they probably can’t do a whole lot to stop it.

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