Transcription into Korean

Foreign words when used in Korean undergoes transcription, to make them pronounceable and memorable. Transcription into Korean, for the most part, is very similar to or even influenced by transcription into Japanese, although the number of homophones resulted by imperfect mapping of foreign sounds onto native sounds is significantly smaller, as Korean has a larger phoneme inventory and a more inclusive phonotactics.
Practicalities of transcription.
The typical syllable structure of Korean is CGVC, with C being "consonant", G "glide", and V "vowel". Consonants and glides are optional. A few English words may get irregular transcription treatment, likely due to the influence of Japanese. Eg: "shirt" → 샤츠 "sya-cheu (Japanese シャツ "sha-tsu); "mother" → 마더 "ma-deo" (Japanese マザー "ma-za-a"); "dragon" → 드래곤 "deu-rae-gon" (Japanese ドラゴン "do-ra-gon"); "level" → 레벨 "re-bel" (Japanese レベル "re-be-ru").
For the most part, transcription into Korean is phonemic, i.e., based on the phonologies of both the source and the target languages (Korean itself). However, [l], an allophone of /r/ in Korean, is utilized syllable-finally and intervocalically to transcribe the foreign sound /l/. This makes the foreign sound /l/ more transcribable into Korean than it is into Japanese, which has no strategic differences between [l] and /r/. E.g.: "ball" → 볼 "bol (Japanese ボール "bo-o-ru); "gallon" → 갤런 "gal-leon" (Japanese ガロン "ga-ron"). Note that [l] is always geminated intervocallically in transcriptions. E.g.: "Hellen" → 헬렌 "Hel-len". Syllable-initially, the foreign liquid sounds /r/ and /l/ are rendered as /r/. E.g.: "right" and "light" → 라이트 ra-i-teu" (Japanese ライト ra-i-to")
Consonants and vowels are transcribed to the native ones that approximate them the most, because, of course, Korean does not have all the sounds of all languages, nor has it developed any new sounds due to recent linguistic contact like Japanese with new sounds like /f/ or even /v/. E.g.: "father" → 파더 pa-deo" (Japanese ファザー fa-za-a". Particularly, transcription into Korean tend to be more conservative as it only employs available hangul syllables, rather than establishing new, non-native combinations like Japanese. For example, the English word "warrior" is transcribed into Korean as 워리어 "wo-ri-eo" using 워, a pre-existing syllable composed of ᅮ "u" and ᅥ "eo", rather than with a combination of "u" and "o"; in contrast, it is transcribed into Japanese as ウォリアー "wo-ri-a-a", using ウォ, a non-native combination. On another note, the foreign phoneme /v/ is always transcribed as ᆸ "b(eu)" (native) into Korean, but as either "b(u)" (native) or "v(u)" (non-native) into Japanese.
Consonants.
Like Japanese, Korean does not allow any consonant clusters other than CG, therefore, when foreign words with such clusters are transcribed, the clusters are broken down and distributed among several syllables. For example, the English word "brand" is transcribed into Korean as 브랜드 beu-raen-deu" (compare Japanese ブランド bu-ra-n-do"), wherein the sequence "bran" is broken down into two syllables, "beu-raen". In these cases, a vowel ㅡ "eu" is inserted in between the consonants of the cluster (compare Japanese "u", "o").
Korean has seven consonants that can occur at the end of a syllable and that are used in transcriptions. Those are /p/, /t/, /k/, /r/, /m/, /n/ and /ŋ/. /p/, /t/ and /k/ generally represent foreign voiceless consonants, although /p/ and /k/ (rendered using jamo ㅂ and ㄱ) occasionally denote voiced consonants, too. E.g.: "lab" and "lap" → 랩 "raep"; "deck" → 덱 "dek". Foreign /t/ is variously rendered as ㅅ or 트 "teu". E.g.: "secret" → 시크릿 "si-keu-rit; "set" → 세트 "se-teu. Foreign /p/, /t/, /k/ are rendered using jamo ㅂ, ㅅ, ㄱ if the preceding foreign vowel is short, but generally using 프 "peu", 트 "teu", 크 "keu" if that vowel is long or a diphthong. E.g.: "map" → 맵 "maep (Japanese マップ "ma-p-pu), but "mark" → 마크 "ma-keu (Japanese マーク "ma-a-ku) and "type" → 타이프 "ta-i-peu (but also 타입 "ta-ip) (Japanese タイプ "ta-i-pu). Foreign /l/, /m/, /n/, /ŋ/ are always rendered using jamo ㄹ, ㅁ, ㄴ, ㅇ, regardless of the quality of the preceding vowel. E.g.: "Tom" → 톰 "Tom; "time" → 타임 "ta-im".
Syllable-finally, foreign consonants not covered by the seven sounds above are transcribed as Cㅡ C"eu" (C for "consonant"). E.g.: "dead" → 데드 "de-deu (Japanese デッド "de-d-do); "speed" → "seu-pi-deu (Japanese スピード "su-pi-i-do); "five" → 파이브 "pa-i-beu (Japanese ファイブ "fa-i-bu); "life" → 라이프 "ra-i-peu (Japanese ライフ "ra-i-fu).
Vowels.
Also, like Japanese, modern Korean lacks diphthongs (ancient diphthongs have all developed into monophthongs). Likewise, foreign diphthongs are broken down and distributed among two syllables. For example, English "eye" is transcribed into Korean as 아이 a-i (compare Japanese アイ a-i), wherein the diphthong /aɪ/ is rendered as "a-i".
Korean has a larger phoneme inventory than Japanese, which allows broader coverage when transcribing foreign sounds. Whereas Japanese uses a single "a" sound for various English sounds such as /æ/, /ɑː/, /ə/, /ʌ/, Korean uses ㅐ "ae" for /æ/, ㅏ "a" for /ɑː/, ㅓ "eo" for /ə/ and /ʌ/. E.g.: "hand" → 핸드 "haen-deu"; "card" → 카드 "ka-deu"; "hunter" → 헌터 "heon-teo". Occasionally, however, the choice of sounds for transcription is influenced by Japanese. E.g.: "brother" → 브라더 "beu-ra-deo" (Japanese ブラザー "bu-ra-za-a"); "dragon" → 드래곤 "deuraegon" (Japanese ドラゴン "do-ra-go-n").
Like Japanese, transcription from English into Korean is largely based on Received Pronunciation (non-rhotic). However, while Japanese still denotes English vowels like /ɑː/ in "car", /ɔː/ in "course", /ə/ in "monster" as lengthened vowels ("a-a", "o-o", "a-a" respectively), Korean ignores vowel length almost entirely, although such length is still indirectly denoted in some cases mentioned above with the use of 프 "peu", 트 "teu", 크 "keu". E.g.: "car" → 카 "ka (Japanese カー "ka-a); "card" → 카드 "ka-deu" (Japanese カード "ka-a-do"); "course" → 코스 "ko-seu" (Japanese コース "ko-o-su"); "monster" → 몬스터 "mon-seu-teo (Japanese モンスター "mo-n-su-ta-a).