Tatar language belongs to Kipchak brunch of Turkic languages of Altaic language family. Like all Turkic languages, Tatar is characterized by vowel harmony and  agglutinative nature of grammatical relations between words. Based on the lexicostatistical matrix of Turkic languages and according to the to recent article in Journal of Language Evolution, Tatar language exhibits more than 50% of basic lexical similarities with at least 12 Turkic languages (Azeri, Bashkir, Crimean Tatars, Kazakh, Karachi, Khakas, Kyrgyz, Turkish, Turkmen, Tuvan, Uyghur, Uzbek). Tatar language has several dialects based on geographical location (Astrakhan, Siberian, Kazan) and on grammatical nuances (Mishar). Crimean Tatar language is much closer grammatically, phonetically and lexically to Turkish language. The modern written Tatar language is based on the Cyrillic script since 1938, prior to that it was in Latin and Arabic scripts, Uyghur writing and ancient Turkic runes.  

Several online Tatar Language Resources available for free (as of December 2021):

Learn

• Tatar Alphabet, Tatar Phonetics and Pronunciation (with English pronunciation parallels)
• 500 Tatar words: online, for iPhone. Sounds of Tatar speech
• Online dictionary: English-Tatar: GoogleTranslate. Russian-Tatar: Ganiev.org, Translate.Tatar
• Engaging Learning materials: AnaTele, Әйдә!Online, Language Heroes ,Tatar with Petrov, Tatar with Ләйсән
• Tatar Grammar: MustGo, Electronic Textbooks by N.Poppe (1963), by G.Burbiel (2018)
• Corpus of Written Tatar (Corpus’ User’s Manual)
• Collection of softwares, applications localized for Tatar language – TatSoft.Tatar 
• Fun linguistic experiment on comprehension of Tatar sentences by Turkish speakers

Read, Listen, Watch

• Animated children’s stories and cartoons: Bala.ru
• Talks on various topics: Elbette.ru
• Electronic books: Baigysh.tatar, WikiBooks
• Audiobooks: Azatliq.org, Tatkniga, Tatar Virtual School
• Internet radio with Tatar classic, folk music and literature citing: Tatarstan Avazy
• Internet and online radio, audio and video podcasts: Kitap.fm
• Internet radio with Tatar modern pop and folk music: Tartip FM
• Online radio of alternative Tatar music: UrbanTatar
• Daily news podcasts on Tatar: TRT

Selection of Tatar Music

• Iconic Tatar singer Ilham Shakirov sings song “Chulpan” (“Morning Star”)
• Beautiful songs by Saida Mukhametzyanova in the capturing Tatar settings
• Fun folk song “Almagaschlarim” (My Lovely Apple Trees) and dance by ZuLayLa
• Lesson on how to dance Tatar Folk dance 
• Elsa Zayari and Artur Islamov concert with numerous beautiful Tatar songs
• Folk song “Su Buylap”(“Along the Idel river”)
• Tatar classical music by DuoMong (from the Netherlands)
• Works by Tatar composer, multi-instrumentalist Adeliia Faizullina (from USA)
• Beautiful Soviet-era Tatar song “Min sine shundyi sagyndym” (“I missed you so much”) in modern interpretation of young singers Saida and Ilnar with views of Kazan city
• Tatar Folk Songs Interpretations by cellist Elena Korableva