Palatal approximant

The voiced palatal approximant is a type of consonantal sound used in many spoken languages. The symbol in the International Phonetic Alphabet that represents this sound is $\langle\rangle$. The equivalent X-SAMPA symbol is j, and in the Americanist phonetic notation it is $\langley\rangle$. Because the English name of the letter J, jay, does not start with $\langle\rangle$, this approximant is sometimes called yod instead, as in the phonological history terms yod-dropping and yod-coalescence.

The palatal approximant is the semivocalic equivalent of the close front unrounded vowel. The two are almost identical featurally. They alternate with each other in certain languages, such as French, and in the diphthongs of some languages, $\langle\rangle$ and $\langle\rangle$ with the non-syllabic diacritic are used in different transcription systems to represent the same sound.

In the writing systems used for most of the languages of Central, Northern and Eastern Europe, the letter j denotes the palatal approximant, as in German Jahr 'year'. This is the IPA usage, and although it may be counter-intuitive for English speakers, it does occur with this sound in a few English words, such as hallelujah and Jägermeister.

In grammars of Ancient Greek, the palatal approximant, which was lost early in the history of Greek, is sometimes written as $\langle\rangle$ (iota with the inverted breve below, the non-syllabic diacritic or marker of a semivowel).

Features
Features of the palatal approximant:

The type of approximant is glide or semivowel. The term glide emphasizes the characteristic of movement (or 'glide') of /j/ from the /i/ vowel position to a following vowel position. The term semivowel emphasizes that, although the sound is vocalic in nature, it is not 'syllabic' (it does not form the nucleus of a syllable).