Apples are arguably the world's most popular fruit -- "the apple of my eye," "as American as apple pie," "an apple a day keeps the doctor away." In many languages, other fruits and vegetables are defined in terms of apples, like pommes de terre in French and sib zamini in Farsi for potatoes, and the Medieval name "love apples" for tomatoes. And let's just say you won't find watermelons in the origin stories of multiple religions.

Along with peas, broccoli and cauliflower are vegetables that are easy to malign when cooked poorly -- "stale and murky," our senior editor Kristen calls them. But treated right in a slaw, a batch of roasted vegetables, or pesto, broccoli, cauliflower, and their ilk can be downright classy. Today we tackle a bevy of brassicas, floret by floret.

Mushrooms aren't vegetables at all -- they're fungi! More specifically, they're the fungus' spore-bearing fruit body, also called the sporocarp, which produces the spores that grow into more mushrooms. While many mushrooms are poisonous, hallucinogenic, or medicinal, the ones we'll be discussing today are all perfectly edible (also, delicious).

Parsnips aren't the most welcoming vegetable -- after all, they look like carrots after an attack by Bunnicula! But strip away that winter-toughed peel and you're left with a white vegetable that's gently sweet and almost honey-like when cooked.

There's something of The Strange Case of Dr. Jekyll and Mr. Hyde about cabbage. One minute it's crunchy and perky, brightening up your burger with a simple slaw, and the next minute it's gone slack, tender, and sweet in a stew or a braise. They're also famous internationally for their pickling affinity, from sauerkraut to kimchi.

Recently, we learned all about hot peppers. Today we turn to their mild-mannered cousin, the bell pepper. Crunchy when raw, meltingly sweet when roasted, bell peppers come in a rainbow of colors. And unlike other peppers, which vary in heat depending on factors ranging from their species to the weather, you'll never find a hot bell pepper: due to a recessive gene, they don't produce capsaicin, the chemical that causes spiciness.

How many types of grape are there? If you answered two -- "red" and "white," aka purple and green -- well, you're not the only one. In reality, there are hundreds of grape varieties used in wine-making, but even at the best farmers' markets you'll only find a handful of different types of "table grapes," as the snacking varieties are called.

To the uninitiated, spiciness is binary: just hot or mild. When you look closer, though, you'll find that "spicy" can encompass fruity, meaty, and citrusy flavors. Today we're looking at 9 spicy members of the plant family Capsicum -- hot peppers -- and how they differ from each other.

Radishes -- peppery, perky, and dependable -- are easy to take for granted. They're among the first green vegetables to appear in the spring and one of the last to disappear come winter, so it's easy to pass them up in favor of other more glamorous brassicas, to say nothing of lettuces and nightshades.

Although tomatillos are only a distant relation of the tomato -- they're actually in the same genus as cape gooseberries and husk cherries -- it's true that the similarities between the two can't be missed. Their affinity for salsa, for example, or the complex flavors they take on after roasting. After all, they're both members of the nightshade family. But the similarities end there.