Tosafot

Klalim

Jargon

1. Beyond the surface level understanding of their words, the Rishonim imbued layers of implicit teachings in their words. There is often what to learn from inference, in addition to the basic understanding.
2. Sometimes Tosafot will argue "Ein Lehakshot" - not to pose a question - but not provide the reasoning, thereby leaving it to the reader to derive the answer or they find it in a parallel Tosafot.
3. Even though Tosafot often poses a question with "Im Tomar" and answers it with "Yesh Lomar," there are instances where the question will be asked in the formal manner but left unanswered.
4. If the primary answer presented to Tosafot's question suffers from a difficulty, an alternative answer will often be offered, prefaced by "הבה מצי לשנויי" or "הבה מצי לתרץ", that isn't subject to the other answers difficulty. This alternative answer, however, is not accepted, as it itself is vulnerable to a much greater challenge, which only the primary answer is safe from. In other words, if the main answer isn't perfect, another, weaker answer that resolves the difficulty with that answer will be suggested but not accepted, because it's subject to much stronger questions.
5. In instances where two answers are offered without quoting one of the Baalei HaTosafot by name, the second answer will only be prefaced with "ועוד" if it doesn't directly contradict the previous one. If the first answer is by a named Baal HaTosafot, though, then the word "ועוד" would be appropriate regardless of the answer, to indicate that this answer is also from the aforementioned Baal HaTosafot.
6. In terms of deciding which of two answers to follow, the Sheyarei Kenesset HaGedolah claims the first answer is ikar; the Chazon Nachum disagrees.
7. Sometimes Tosafot will pose a question with "Teimah" and leave it unanswered but not also "VeTzarich Iyun," because the answer was obvious.
8. Rabbeinu Chananel's rulings are cited as a means of resolving a sugya.

Authorship

1. It is not uncommon to discover contradictions between comments of Tosafot across different Masechtot. For example, in one place, Tosafot will leave a question unresolved, while, in another place, it will be answered, and stil, in another location, a different answer will be presented and the other one rejected. Each side of that contradiction is in fact representing the opinion of a different Baal HaTosafot. Similarly, when two Poskim each associate a different understanding with Tosafot, one could explain that they're referring to different Baalei HaTosafot.
2. Even within a Masechet, sometimes there are missing comments of Tosafot or comments of other Baalei HaTosafot mixed in, the latter of which leads to contradictions within one set of Tosafot comments. Regardless, we try to reconcile the differences as much as possible.
3. The Maharshal has a well known illustration of how Rabbeinu Tam had around eighty students of incredible caliber.
4. The Tosafot commentary on most of the Masechtot studied originates with the Tosafot compiled by the Rash MiShantz, a compilation known as the Tosafot Shantz. However, our version was abridged by R' Elazar Tukh, whose redaction is known as the Tosafot Tukh and whose goal was to elucidate the give and take of the Gemara, not decide Halacha. Nevertheless, we follow the Tosafot Tukh over the Tosafot Shantz, because the Tosafot Tukh came later.. In fact, some say that we should follow the Tosafot on the more major masechtot, such as Yevamot, over the Tosafot on smaller Masechtot, because the former are from the Tosafot Tukh.
5. The Tosafot commentary to Yoma comes from the Maharam Rutenberg.
6. There is a debate if Tosafot and Rabbeinu Tam are considered two separate entities or not with respect to Kim Li and other Halachic calculations.
7. Most of the Mordechai, Rosh, Samag, Samak, Sefer HaTerumah, Hagahot Maimoniot, and Rabbeinu Yerucham is based on the Tosafot.

Misc.

1. Chochmei HaTzarfatim according to many refers to Baalei HaTosafot, although some are unsure.

Baalei HaTosafot of Note

1. Rabbeinu Elchanan is the son of the Ri.
2. "Rabbeinu Porat" is the Rashbam's son.

See Also

1. Raavan
2. Rabbi Eliezer MiMitz
3. Rash MiShantz
4. Samag
5. Sefer HaTerumah
6. Maharam Rotenberg
7. Mordechai
8. Hagahot Maimoniot
9. Rosh
10. Ra'avyah