This letter always represents the ipa vowel /y/, never the consonant /j/ that y sometimes represents in modern english. Old english texts often include a tittle above the letter: Y!mobile(ワイモバイル)のyoutube公式チャンネルです。 y!mobile(ワイモバイル)のyoutube公式チャンネルです。.more ymobile.jp and 2 more links
Ultimate Guide to CSS Grid & Flexbox Building Layouts