Korean Alphabet - Basic Consonants

The consonants can change in sound.  If it is in front, it has a harder sound, for example ㄱsounds like 'k'.  But when there are vowels in front, it is softer, ㄱ sounds like 'g'.
Pronounciation guide: http://www.genkienglish.net/speakkorean/koreanalphabet.htm