Coming back to Canada, I've been sort of surprised by how many misconceptions people have about what teaching in Korea is like. For the most part, people assume that teaching in Korea is much the same as teaching in Canada -- that you are in a classroom in a proper school teaching a class of your own, using Western teaching methods and practices. Strangely enough, because I'll be working at an international school, my job will actually fit this misconception. It would appear that I am the exception that proves the rule. But as an employee of an international school, I am actually part of a very small minority on the Korean ESL teaching scene.
My attempts to explain to Canadians just how different schooling is in Korea have generally been unsuccessful. When I tell people here how much the Korean education system is reliant on rote memorization and test scores, people just say, "Oh, well, it's like that here too." But that is not the case. While Canadian schools put some emphasis on memorization and tests, the two systems cannot be compared, and most Canadians simply lack the frame of reference to understand what the average Korean student's day is like, or the sort of employment situation that most foreigners are walking into.
The three main Korean employers of foreign teachers are hogwons, public schools, and universities. Hogwons, by and large, are the biggest employer of foreigners in the country. They are everywhere. There might be two dozen or more of them on any city block. They are privately run businesses intended for education (similar to Japanese "cram schools"). Koreans are obsessed with education and will do anything they can to make sure their children get ahead, which means enrolling them in multiple hogwons after the regular school hours to give them a leg up. Conditions at hogwons vary widely. I have some friends who are very happy with their hogwon jobs and have stayed for many years, but I have also heard horror stories -- you can find a "hogwon blacklist" online that warns potential teachers away from the worst ones. One of the major downsides of hogwons is that you hardly get any vacation time -- five days if you're lucky, and they're not necessarily consecutive. Hogwons make up the backbone of the Korean economy. Most foreign teachers work at hogwons. They usually work evenings though, so I was only able to see my hogwon teaching friends on the weekend or holidays.
In the past few years, public schools have also become really popular for foreign teachers. They are generally pretty good gigs, as you get more vacation time and fewer contact hours than at hogwons. When you work at a public school you teach a class jointly with Korean teachers. It can sometimes be a source of trouble if the Korean teacher is insecure about their level of English, but it can also work out really well. It just depends on where you are.
University jobs are very highly sought on the ESL scene because they have a reputation for low contact hours, good pay, and ample paid vacation (sometimes four or five months). Unfortunately, over the last few years the quality of university jobs in Korea has been steadily declining. The pay is getting lower, contact hours are rising, and vacation is disappearing. (At public schools and universities, vacation time is becoming a contentious issue, as employers are starting to demand that foreign teachers do additional "camps," something with extra pay, sometimes not.) Good university jobs with ample vacation and good pay can still be found, but the problem I ran into is that a lot of these employers assume that their employees will be "lifers" (which I am not) who already have their own housing. Koreans have quite a different real estate system than North Americans. Getting a decent apartment in Korea generally requires a deposit of at least $30,000. You get it back when you move out, but I was only planning on 2-3 years, tops, and I didn't exactly have that money kicking around the way a lifer would. Also, even though furniture and appliances are cheap over there, it's still a big expense to furnish a place you only plan to inhabit for a year or so.
Aside from the opportunity to assist students in an effective way, the housing and vacation issues were one of the reasons the international school circuit appealed to me. We are given what sound like very nice apartments. Also, we still have generous vacation time and do not have to worry that it will be taken from us.
If you are interested in getting a sense of what hogwon jobs generally entail, you can check out this really popular job board. There are postings for hogwons, public schools, and universities here.