Maturing into a range of different colours and spices, chillies are graded according to the 'Scoville scale', which the American pharmacist Wilbur Scoville, created in 1912, to indicate the amount of capsaicin in a variety of chilli peppers.
Capsaicin is the chemical compund that produces the characteristic heat sensation in the mouth and the amount present is measured in Scoville Heat Units (SHU).
Whether you're looking to add a gentle amount of spice to your food or you're ready for an eye-watering, fiery challenge, here are the top 10 chillies in order of heat.
1. Sweet bell pepper
While pure capsaicin is an explosive 16 million SHU, back at the other end of the scale, the lowly supermarket sweet bell pepper has a Scoville rating of zero; so no danger there.
The pimiento - often to be found stuffed in Spanish green olives - rates 100-900 SHU.
3. Rocotillo pepper
Up a grade from this, in the 1,000-2,500 SHU range, is the Peruvian Rocotillo pepper, which is usually green or yellow.
That well known condiment, Tabasco sauce, scored 2,500-5,000 SHU (so use it sparingly in your Bloody Marys).
Around this level is also to be found the jalapeño (apparently named after the Mexican town of Xalapa, where it originated), which can range from 2,500-10,000 SHU.
5. Cayenne pepper
Staying in the kitchen, but on a much higher shelf - Scoville-speaking - is cayenne pepper, which registers at 30,000-50,000 SHU.
6. Bird's eye chilli
That staple of Thai and Keralan cooking, the Bird's Eye Chilli, meanwhile, clocks in at 50,000-100,000 SHU.
7. Scotch Bonnet
Caribbean cuisine, by contrast, favours the Scotch Bonnet, pictured, known in Guyana as 'Ball of Fire' (100,000-350,000 SHU).
Similarly fiery is the magnificently named Madame Jeanette, a small but fiery reddish-yellow bell pepper from Suriname (also 100,000-350,000 SHU).
8. Red Savina pepper
The Red Savina pepper has been developed from the well-known habanero chilli, to produce hotter fruit (are these people insane?).
Characterised by a deep red colour, it registers between 250,000 and 450,000 SHU.
9. Bhut Jokolia
If you are travelling in Northeast India or Bangladesh, be very careful if anyone tries to tempt you with a curry containing the Bhut Jokolia.
It's also known as the 'Ghost Pepper' - which is what you'll feel like after tasting it, as it is rated at over 1 million SHU.
10. Trinidad Moruga Scorpion
And at the top of the chilli tree (well, plant) is the exceptionally hot Trinidad Moruga Scorpion. This golf-ball-sized beast has been identified as the world's hottest cultivated chilli pepper.
Despite its initially sweet taste, the fire builds and builds, and can rate as high as 2 million SHU.