Fermentation is an ancient practice that makes foods more nutritious, delicious and edible that got lost for awhile in the nasty colonization of North America. Fermented foods and drinks can be found as part of traditional diets of all cultures all over the world (maybe you're studying today and looking for some procrastination material?) and there's a seriously awesome revolution on the rise amongst the renegades of healthy eating to work it back into the standard N.America diet (also known as SAD). Lots of things we regularly consume are fermented - you know that, right? Beer, wine, yogurt, cheese, fish sauce, hot sauce... Sadly, the more common place these items are, the less likely they are to be teeming with delicious Lactobacillus and other friendly fermenters, and the more likely they are to have processed acidic substitutes instead. The good news is that quality fermented foods have recently started to become available at grocers everywhere - the better news is that doing your own fermenting is dead easy.
I have been a proud SCOBY caretaker for the past 6 years and I have only just - just - perfected my kombucha to be the bubbly effervescent drink I'm so willing to drop $4 on at every health food store I visit*. Fermentation is truly an art, and it takes a certain amount of research and practice, sure - but also confidence! I learned from Sandor Ellix Katz at the beginning of my experimentation with fermentation that it's important to employ all your senses when trying to ferment, and not to be afraid to taste things along the way - unless your nose directs you otherwise (to the garbage can I mean). If you pay attention to what you're doing, the chances of consuming something not fit for consumption are seriously slim to none. Case-in-point - a batch of sauerkraut I had going in my crock late last summer ended up stewing a little too long and smelled more like an old sock than any food ever should. I tasted it anyways (my experience has left me bold) - not good. Not good! But that's ok! Next time, I'm not letting it sit so long in 35degC weather. Simple.
Fortunately, most of the things that we love to ferment are fairly inexpensive - I mean one cabbage will run you about $1.50 and make ~3 L of sauerkraut - so don't be afraid to abandon ship and start over when things go awry; it's worth it to keep on experimenting. Don't get discouraged, but do reach out for help - there are plenty of excellent resources available to anyone who's looking (1, 2, 3, 4, 5) - try and think about what "went wrong" (there's really no 'wrong') and switch it up next time.