How do the Torah, Mishnah, Talmud and Gemarra relate to each other?

Are there even more things require to full understand the Torah?

um well they are all books written because people wanted answers for the unexplained so they made some fake stories and said there was a god and said that he was watching you and this controlled peoples lives and it kept social order God is FAKE LOL LOL LOL OWNED

The Torah is the Scriptures and the Talmud is commentary on the Torah and it is made up of the Mishna and the Gemarra plus a few more writings of the Rabbis etc.

The Torah is the five books of Moses. It's what's written on the scroll that Jews read from in synagogue.

That is called the "written Torah". It was transmitted orally until Ezra's time.

The rest of the revelation at Sinai was not written down at that time. It continued to be passed on orally, and is called the "oral Torah". This was eventually written down in the Mishna during the Babylonian Exile.

The Talmud is made up of the Mishna and the Gemara. The Gemora is a collection of commentaries on the Mishna.

On a page of the Talmud, there is the Mishna page in the middle, with the Gemara and the commentaries all around it.

(This can get confusing, especially when someone refers to something "written in the oral Torah.")

Another word you might want is the Tanach.

The word "Tanach" is a three-letter acronym in Hebrew. (Only the consonants count, and the "ch" is one Hebrew letter.)

The "T" in Tanach stands for the Torah, which is another name for "the Five Books of Moses." That's what's written inside a Torah scroll.

The "N" in Tanach stands for "Neveim", the Hebrew word for "Prophets". This is the collection of books in the Bible about the lives of the prophets. (for example, "Joshua" and "Jeremiah.")

The "Ch" in Tanach stands for "Ketuvim", the Hebrew word for "Writings". This is collection of books in the Bible that has the poetry writings ("Psalms", "Proverbs", "Job") the scrolls ("Esther", "Lamentations", "Ruth", "Song of Songs", and "Ecclesiastes"), and a few others (e.g. "Daniel" and "Chronicles")

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Something else needed to fully understand the Torah is the Midrash. (http://en.wikipedia.org/wiki/Midrash )

There are many very important later commentaries on the Torah that are fundmamental to understanding it. Rashi, Onkelus (author of Targum), the Rashbam, the Ramban (Nachmonides), and Ibn Ezra come first to mind.

These are all available in the Mikraot Gedolot, which is a version of the Torah/Tanach with all these commentaries surrounding the text. http://en.wikipedia.org/wiki/Mikraot_Gedolot

Rashi is from the 11th century b.c.e. and is probably the most important commentary for understanding the plain meaning of the Torah text. http://en.wikipedia.org/wiki/Rashi

Rambam's (Maimonides) Mishne Torah is another fundamentally important text for understanding how the words of the Torah connect with the commandments. (Not to be confused with "Mishna")
http://en.wikipedia.org/wiki/Mishne_Torah (12th century b.c.e.)


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There is also the Arba Tumim (http://en.wikipedia.org/wiki/Arba%27ah_Turim) and the Shulchan Aruch (http://en.wikipedia.org/wiki/Shulchan_Aruch) but these are for advanced study.

(This is not to be confused with the "Kitzur Shulchan Aruch" by Rabbi Granzfried in 19th century Hungary, which is not universally accepted and often harsh, but still an important summary/handbook. http://en.wikipedia.org/wiki/Shlomo_Ganzfried Many people quote obscure and harsh rulings from the Kitzur Shulchan Aruch as though these practices were universally accepted. They're not.)

A summary of these is in the Mishna brura (not to be confused with the Misnah or Rambam's Mishna Torah) which is the Chofetz Chaim's summary of the Shulchan Aruch, and helps clarify how Jewish law is applied. (http://en.wikipedia.org/wiki/Mishna_Brura) It is considered authoritative and reliable by many ashkenazim.

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EDIT: In response to "Are there even more things require to full understand the Torah?" I left out something important:
A study partner!

We learn by interacting with the text, not just reading it. In order to do this, you need someone else with whom to study.

Torah is the Chumishei Sifrei Moshe, The Five Books of Moses.

Mishne is the or la commentary given to Moses, by God, on Sinai. It was written down after the destruction of the second temple to prevent i getting forgotten or lost. Thus it is taught in the form of How the Rabbis put across the law.

Gemorrah is the later commentary by Rabbis on the Mishnah and includes many Beraisos. A Beraiso is an oral teaching from the time of the Mishnah that was not recorded as a Mishnah. braises are foten brought to teach additional information about a Mishnah, to resolve disputes in a Mishnah or to introduce new issues and complications into discussions in order for them to be resolved.

The Talmud is the collected Mishanyot with their associated Gemorrahs. Mot all Mishnah's have Gemorrahs and not all sections of the Mishanh appear in the Talmud as a result of this. In modern Talmuds the margins, headers and footers have different Rabbinical commentaries, with rashi and tosafos being the primary ones (one exception to this is Masechta Nedarim where the commentary of the Ran replaces that of rashi in many editions since there is a question on the accuracy of the Rashi we have for that Masechta.)

Other things necessary:
Midrash- oral teachings on the Torah in various collections. These are both allegorical stories and halachic stories to illuminate how certain practices from the Torah should be understood.
Nevi'im- the books of the prophets. We do not derive halachah from here (halachah can only be derived from the Torah and Mishnah. However, we do see how to understand and apply some halachos fromthere, and there is of course the other information found in the prophecies and visions of the prophets.
Ketuvim- writings- Like Nevi'im this is not a source for Halachah, but for understanding application and how to apply them. various lessons can be learnt from the psalms, propverbs etc.

On an even deeper level- you are going to have to look at the mystical side contained in the commentaries of the Torah found in the Zohar, Sefer Yetzira and Sefer Behir. Please stay away from the cults on this one- tere are alot of people ready to con you out of your money to teach you Kaballah!

For a FULL understanding- well, for that you need to be God!