The whole picture
Oolong is the partially oxidized category, and it is the widest of the six.
The maker withers the leaf, then shakes it and rests it in repeated rounds.
That step, called making the green（做青）, bruises the leaf edges and starts oxidation there.
Oxidation is then stopped by fixing, at whatever point the maker wants.
The result can sit anywhere between roughly 20 and 70 per cent.
That range is wider than in any other category, and it is why oolong resists one sentence.
Most oolong is then rolled, dried, and in many cases roasted.
Shape follows region: tight balls in Anxi, twisted strips in Wuyi, long curls in Taiwan.
Anxi makes Tieguanyin（铁观音）, the best known ball rolled style.
Wuyi makes yancha（岩茶）, roasted strip teas grown on rocky slopes.
Chaozhou makes dancong（单丛）, taken from individual old bushes and named for their aromas.
Taiwan makes both high mountain ball styles and heavier roasted ones.
The cup runs from fresh orchid and butter at the light end to charcoal, wood and dark sugar at the heavy end.
Roasted oolong also keeps and improves with time, which the light styles do not.
How to approach it
Learn one idea first: oxidation here is a dial, not a fixed setting.
Every other distinction in the category is a position on that dial plus a roast level.
Once you can place a tea on both axes, the names stop being confusing.
Then meet four archetypes rather than a hundred names.
A light ball rolled Anxi style, a medium roast, a heavy roast Wuyi style, and a dancong.
Tasted together, those four cover the whole category.
Ask about the roast before buying, since it decides almost everything about the cup.
A heavy roast hides a mediocre leaf, which is why cheap roasted oolong is so common.
Ask when it was roasted, because a fresh roast tastes hot and needs a few months.
A roasted oolong drunk straight from the roaster tastes of the oven rather than of the tea.
Light styles should be bought young, drunk quickly and stored cold.
Roasted styles can sit at room temperature for years and often improve.
Mixing those two storage rules is the fastest way to ruin a good purchase.
Buying and brewing
Oolong is brewed in two quite different ways, and both are correct.
Gongfu service uses a high leaf ratio: 7 g in a 110 ml gaiwan.
Water goes in at 95 °C and the steeps are short, around 20 seconds.
That method produces 8 or more infusions, and the tea changes across them.
Western service uses one pot, around 5 g for 300 ml, and a longer steep.
That method is simpler and flatter, and it is what most households actually do.
Use the gongfu method when the tea is the point, and the pot when it is not.
Preheat the vessel either way, since a cold gaiwan costs you the first steep entirely.
Keep a timer visible, because counting in your head fails by the fourth steep.
Buy 50 g of three different roasts rather than 150 g of one.
The comparison teaches more than any amount of reading about it.
Store light oolongs sealed and cold, and roasted oolongs sealed and dry at room temperature.
Keep both away from spices, since roasted leaf picks up other aromas readily.
A roasted oolong stored beside a jar of curry powder is a lost cause.
Where to go next
The most instructive next step is a roast comparison.
Put a light Tieguanyin next to a roasted Wuyi tea and brew them the same way.
The contrast is the width of the category, measured in two cups.
Then try a dancong, which is where aroma becomes the whole subject.
Names like honey orchid and almond describe a smell, not a flavouring.
Once that clicks, the naming conventions across Chaozhou stop looking strange.
After that, work along the regions: Anxi, Wuyi, Chaozhou and Taiwan, China.
Each region has a shape, a roast habit and a set of named cultivars.
The regional guides here take each of them separately.
The brewing pages cover the gongfu method step by step.
If you want a simpler category, a red tea does the same job with less attention.
Oolong rewards patience, and it gives back more than it asks for.
Three sessions across three roasts is enough to know where you stand.