Hands up who is scared of the dark? Most of us have at some point wondered what might be lurking in the shadows: ghosts, monsters, giant spiders - take your pick. Luckily, we can turn on the lights and immediately banish any imaginary nighttime terrors. Once, though, night was an impenetrable abyss and some horrors were all too real.

Back in the Middle Ages, without street lighting, people were scared to go out at night. Thieves, villains and brigands were everywhere: darkness served as their mask. As well as the ever-present danger of being robbed, or worse, there was the practical concern of tripping over woodpiles or falling into a river.

You weren’t exactly safe indoors either: people apparently used to push the furniture against the wall before going to bed so that they wouldn’t bump into it if they got up in the middle of the night.

So people went to bed when the sun set and got up at sunrise; working, socializing and playing during the hours of sunlight. In fact, that great ball of plasma in the sky ruled their lives.

The advent of candles transformed nighttime from being a very dark place indeed to somewhat murky. Open your fridge door today and you will shed more light than most households enjoyed in the 18th century.

There was a choice of candles to burn: tallow candles were made with the fat of slaughtered animals but smoked, and worse, stank. Beeswax candles cast a steadier light but cost four times as much. Spermaceti candles, made with wax extracted from the head cavities of sperm whales, burned twice as brilliant again but cost even more. The poor, meanwhile, made do with rush lights – meadow rushes cut into strips and coated in animal fat.

The problem with candles was that they had to be tended all the time. Plus, they were a dangerous fire hazard, leading to scores of deaths each year.

So soon the story of human lighting moved on from candles to oil lamps instead. The brighter light from oil lamps made people more sociable in the evenings, allowing them to play parlor games, tell stories, swap gossip or entertain guests. The drawback was that oil was expensive and oil lamps quickly got filthy.

Gas lighting, introduced in the early 19th century, was a superior solution. Before long, its popularity spread. Cities became alive at night, as more people ventured out of their homes under the relative safety of gas streetlamps. There is a reason why “nightlife” is a 19th-century word: suddenly, the middle class could spend their evenings perusing shop windows, visiting theatres and eating out.

It is worth noting here that gas streetlamps at this time gave off less light than a modern 25-watt lamp. They were also fairly spread out, providing distant bright spots to aim for, unlike the illuminated city streets of today.

It was when electric lighting was introduced that the world really lit up. Electric light was instant, abundant and ultimately irresistible. And by 1900 electric lighting had become the norm in cities.

For over a century now, electric light has lit up our homes, streets and offices, and extended our work and leisure time into the night, whether watching an international football match in a stadium or catching the latest movie.

Recently, we have even started using light to transform our mood. Most people suffer from a touch of the blues during the winter months: too little daylight drags us down, making us feel depressed and tired. It’s a lot more severe for those suffering from Seasonal Affective Disorder (SAD), a psychological disorder characterized by depression, tiredness and sometimes even suicidal thoughts. Thankfully, sitting for 30 minutes in front of a light therapy lamp gives a biological boost to SAD sufferers by prompting the production of melatonin and regulating circadian rhythms (the built-in biological process that oscillates every 24 hours).

Alternatively, for those wanting to brighten up the winter months, how about a trip to the Hotwire (light) Helios Bar in West Seattle? The café has light boxes, whose rays simulate sunlight, perking up customers by adding an extra dose of light to their latte.