What is the meaning of ь?

A letter of the Cyrillic script, called soft sign.

A letter of the Old Cyrillic script, called front yer or yeri.

A letter of the Unified Northern Alphabet, Yañalif and similar orthographies, used during the short-lived Soviet Latinization campaign of the 1930s.
Languages with this letter were Altai (Oyrot), Bashkir, Cherkes, Chukchi, Crimean Tatar, Dungan, Ingrian, Kabardin, Kazakh, Kalmuk, Karakalpak, Karachay, Ket, Khakass, Khanty, Koryak, Kurdish, Kyrgyz, Mansi, Nogai, Oyrot, Permiak, Selkup, Tabasaran, Tatar and Turkmen.

The sixty-eighth letter of the Abaza alphabet, written in the Cyrillic script.

A letter of the Abkhaz alphabet, written in the Cyrillic script.. Palatalizes a preceding consonant letter.

The sixty-first letter of the Adyghe alphabet, written in the Cyrillic script.

The fiftieth letter of the Aghul alphabet, written in the Cyrillic script.

The thirty-sixth letter of the Alutor alphabet, written in the Cyrillic script.

The thirty-third letter of the Buryat alphabet, written in the Cyrillic script.

The thirty-third letter of the Chukchi alphabet, written in the Cyrillic script.

The forty-third letter of the Dargwa alphabet, written in the Cyrillic script.

The thirty-fifth letter of the Dungan alphabet, written in the Cyrillic script.

The thirty-third letter of the Eastern Mari alphabet, written in the Cyrillic script.

The thirty-third letter of the Even alphabet, written in the Cyrillic script.

The thirty-first letter of the Evenki alphabet, written in the Cyrillic script.

The forty-first letter of the Ingush alphabet, written in the Cyrillic script.

The forty-fourth letter of the Itelmen alphabet, written in the Cyrillic script.

The fifty-fifth letter of the Kabardian alphabet, written in the Cyrillic script.

The thirty-sixth letter of the Khakas alphabet, written in the Cyrillic script.

The thirty-sixth letter of the Kumyk alphabet, written in the Cyrillic script.

The thirty-third letter of the Kyrgyz alphabet, called ичкертүү белгиси (ickertüü belgisi), and written in the Cyrillic script.

The forty-second letter of the Lezgi alphabet, written in the Cyrillic script.

The forty-third letter of the Nivkh alphabet, written in the Cyrillic script.

The thirty-eighth letter of the Northern Mansi alphabet, written in the Cyrillic script.

A letter of the Old Novgorodian alphabet, written in the Old Cyrillic script.

The thirty-fourth letter of the Southern Altai alphabet, written in the Cyrillic script.

The forty-third letter of the Tabasaran alphabet, written in the Cyrillic script.

The thirty-first letter of the Tundra Nenets alphabet, written in the Cyrillic script.

The thirty-fourth letter of the Western Mari alphabet, written in the Cyrillic script.

The thirty-seventh letter of the Yakut alphabet, called сымнатар бэлиэ (sımnatar belie), and written in the Cyrillic script.

The forty-third letter of the Avar alphabet, written in the Cyrillic script.

The thirty-eighth letter of the Bashkir alphabet, written in the Cyrillic script.

The twenty-ninth letter of the Belarusian alphabet, written in the Cyrillic script.

The twenty-eighth letter of the Bulgarian alphabet, called ер малък (er malǎk), and written in the Cyrillic script.

The forty-third letter of the Chechen alphabet, written in the Cyrillic script.

The thirty-fourth letter of the Chuvash alphabet, written in the Cyrillic script.

The thirty-fourth letter of the Crimean Tatar alphabet, written in the Cyrillic script.

The thirty-sixth letter of the Kalmyk alphabet, written in the Cyrillic script.

The thirty-ninth letter of the Kazakh alphabet, written in the Cyrillic script.

The thirty-second letter of the Mongolian alphabet, called зөөлний тэмдэг (zöölnii temdeg), and written in the Cyrillic script.

The fortieth letter of the Ossetian alphabet, written in the Cyrillic script.

The twenty-eighth letter of the Moldovan alphabet, written in the Cyrillic script.

The thirtieth letter of the Russian alphabet, called мягкий знак (mjaxkij znak), and written in the Cyrillic script.

The thirty-sixth letter of the Tatar alphabet, written in the Cyrillic script.

The thirty-third letter of the Tuvan alphabet, written in the Cyrillic script.

The thirty-fifth letter of the Udmurt alphabet, written in the Cyrillic script.

The thirty-first letter of the Ukrainian alphabet, called м’який знак (mʺjakyj znak), and written in the Cyrillic script.

The twenty-eighth letter of the Uzbek alphabet, written in the Cyrillic script.

Source: wiktionary.org