Ṭā Ha (/ˈtɑːˈhɑː/; Arabic: طه) is the 20th chapter (sūrah) of the Qur'an with 135 verses (āyāt). It is named "Ṭā Hā" because the chapter starts with the Arabic letters: طه (Taha) which is believed one of the names of the prophet Muhammed (PBUH). Luxenberg's perspective is that the letters Ta-Ha could mean "marvel" or "be amazed!" in Aramaic.

Regarding the timing and contextual background of the revelation (asbāb al-nuzūl), it is traditionally believed to be a Meccan / Makki surah, from the second Meccan period, which means it is believed to have been revealed in Mecca (Makkah), instead of later in Madinah.

Among the subjects treated in this chapter are God's call of Moses, the Exodus of the Israelites and the crossing of the Red Sea, the worship of the Golden Calf and the Fall of Man. The main theme of the chapter is about the existence of God. It addresses this theme through stories about Moses and Adam. Surat 20 displays several thematic and stylistic patterns described by Angelika Neuwirth in Jane McAuliffe's book "The Cambridge Companion to the Qur'an." These include the eschatological prophecies of the Quran, signs of God's existence, and debate. Additionally, sura 20 employs what has been termed the "ring structure" to reinforce its central theme.

This is the Chapter that convinced Hazrat Umar (R.A) to convert to Islam.

Structure:
The first two words of Chapter 20 are Ta Ha.

Sura 20 focuses upon one theme, and is structured in such a way as to reinforce this theme repeatedly. Surat / Sorat 20 begins with an introduction which proclaims the greatness of God. In the body of the surah, there are two distinct stories, one about Moses and one about Adam, each of which is broken into smaller sections. Both stories are prefaced by instructions from God to Muhammad, and followed by a discussion of judgment day and the punishment of the disbelievers. To conclude the sura, there is another section restating and reinforcing the main theme, followed by a brief instruction to Muhammad (PBUH). This repetitive pattern is what Carl W. Ernst terms the ring structure in his book "How to Read the Qur'an" The first part of the sura, up until the story of Adam, and the second part are, thematically and structurally, copies of each other. The story about Moses gives a much longer, more detailed description to introduce the theme, and the shorter story of Adam serves to summarize and repeat the theme already discussed. The introduction and conclusion paragraphs, including the verses where God addresses Muhammad, are the bookends to the sura, and bind the stories together.

The Prophet(S.A.W) said “Whoever reads a letter from the Book of Allah will receive a hasanah(good deed) from it, and the hasanah is multiplied by ten. I do not say that Alif-Laam-Meem is a letter , rather Alif is a letter, Laam is a letter, and Meem is a letter.” (At-Tirmidhi).

So here is a hadith (hadees / hadis) on the benefits of Surah Ta Ha:

Abu Hurairah (radiAllahu anhu) reported that Allah’s messenger (PBUH) said, A thousand years before creating the heavens and the Earth, Allah recited Ta-Ha and Ya-Sin, and when the angels heard the recitation they said, ‘Happy are the people to whom this comes down, happy are the minds which carry this, and happy are the tongues which utter this. [Darami transmitted it, at-Tirmidhi]

Abu Umamah (radiAllahu anhu) reported that the messenger of Allah (salAllahu alayhi wasalam) said, “The greatest name of Allah, which if He is called by it, He responds, is in three surahs: Al Baqarah, ‘al Imran and Ta-Ha.”

Surat taha merupakan surat ke-20 dalam Al-Qur’an dan tergolong surat Makkiyyah. Surat ini terdiri atas 135 ayat dan dinamai surat thoha karena permulaan ayatnya diawali dengan kata “thoohaa”.

طه،بیستمین سوره قرآن است که مکی و 135 آیه دارد.
در فضیلت این سوره از پیامبر اکرم صلی الله و علیه و آله و سلم نقل شده: «به کسی که سوره طه را قرائت کند، در روز قیامت ثواب همه مهاجران و انصار اعطا می شود».