Gemara

6a (Mishnah): If Kemitzah was done with the left hand, it is Pasul;

Ben Beseira says, he returns the Kometz to the Minchah, and does Kemitzah again, with his right hand.

Question: When the Kometz it is returned to the first Kli, that is Mekadesh it, and this completes the Avodah! (It cannot be fixed!)

Answer: The Kometz is not returned to the Kli itself, rather, on the wall of the Kli. The Kli is shaken, and the Kometz reenters the pit (from which it was removed) by itself. It is as if a monkey put it in. (Therefore, the Kli is not Mekadesh it.)

Gitin 20a (Beraisa): "He will write" - he may not engrave.

Contradiction (Beraisa): A Get of freedom written (engraved) on a tablet is valid.

Answer (R. Elazar): If he engraves Yerechos (the shapes of the letters themselves), it is considered writing, but not if he carves out Tuchos (the insides and background of the letters, and leaves the Yerechos raised).

The writing on the Tzitz was engraved.

(Rav Ashi): A die for stamping coins only compress the Tuchos. It does not cause the Yerechos to rise.

60a (Rabah): One may not write a Parshah (i.e. less than a full Sefer) of a Chumash.

Question (Mishnah): Queen Hilni made a gold tablet on which Parshas Sotah was written.

Sotah 48b (Beraisa): We cannot write on the stones of the Efod in ink, for it says "engraved"! One cannot cut them with a chisel, for it says "in their fullness"! Rather, one writes in ink, and the Shamir makes the stone cave in.

Eruvin 35a (Mishnah): If a Zav banged (without touching, e.g. through a stick) on a box, it becomes Tamei;

R. Nechemyah and R. Shimon are Metaher.

(Tosefta): The general rule is, if the Zav's Kocho (impetus) moved it, it is Tamei. If vibrations moved it, it is Tahor.

(Abaye): All agree to this. They argue in a case when the Zav's Ko'ach caused vibrations. The first Tana considers this as if the Zav moved it; R. Nechemyah and R. Shimon do not.

Rishonim

R. Yerucham (Toldos Adam v'Chavah 2:2, 19:2): In a Teshuvah, the Rambam equates engraving to writing. He brings a proof from Gitin 60a. It tried to prove that one may write a Parshah from the tablet on which Parshas Sotah was engraved.

Roke'ach (280): Regarding a Get, we say that engraving is not writing, e.g. if a press compresses Tuchos (and leaves the Yerechos raised). Engraving is forbidden on Yom Tov

Rama mi'Pi'ano (93): A Yisrael who understands Lishmah may write a Get through a printing press l'Chatchilah. Also witnesses may sign this way. I heard that someone disqualified even b'Di'eved, for this is like engraving. I hired many workers and supervised and discovered that this is wrong. Even if the press merely engraved the Yerechos into the paper without ink, this would be Kosher for a Get. For a Sefer Torah, Tefilin or Mezuzah, one must write the letters. One may not engrave even the Yerechos. Our printing is primarily through ink. The parchment is pressed in the press only in order to make the full image of the letter appear on it in ink. We disqualify engraving for a Get because this is not "v'Chosav". The Luchos were engraved, and it says "v'Chosavti Al ha'Luchos"! If one carves out Yerechos in a Get, this is Kosher, like the Luchos. If the letters protrude (and he carves out the Tuchos), like stamping coins, the Gemara disqualifies this.

Rashi (Eruvin 35a DH Machmas and DH v'Hacha): The case of vibration is when the Zav stomped on the floor, and the vibration of the floor moved the Kli. They argue about when the Zav hit the Kli, and it did not move, just it vibrated.

Or Zaru'a (1:563): R. Elyakim explains that to make the Shin on the Tefilin box, one presses on the box from below and it spreads out above on two opposite sides. R. Simchah says that some put the box in a mold with a Shin protruding, and press the box, and (it fills the gap and) a Shin protrudes from the box. This looks more like a Shin than a Shin crumpled from the leather. The Shin is Kosher in any way, even if it came about by itself.

Divrei Chamudos (Hilchos Tefilin 23): Orchos Chayim says that one may not make the Shin through Defus (pressing against the box), for this is like carving out Tuchos. R. Yonah and the Rashba agree. The Beis Yosef says that the Rambam, Rosh and Tur agree. In Ashkenaz they pull out the leather with tweezers to make the Shin. Our custom is to use Defus; Orchos Chayim brings that some do so.

Maharsham (3:357): It is clear from Or Zaru'a that the way we make the Shin is normally not considered writing. However, R. Yerucham and the Rambam forbid entering a bathroom with verses embroidered on a garment, due to disgrace. Get Pashut (125:15) says that many hold that there is Kedushah in every case. Perhaps the Roke'ach would admit. However, photography is different. It is not considered man's action. One opens the shutter, and light that comes through causes chemical reactions in the film. It is Ko'ach Kocho; it is as if a monkey did it, by itself. This is like in Menachos, if the Kometz was returned to the wall of the Kli and he shook the Kli and the Kometz fell in, it is as if a monkey returned it. Rashi in Eruvin says that if one stomped and made the floor vibrate, this is Ko'ach Kocho.

Poskim

Rema (YD 271:7): Some say that one should write a Sefer Torah with a reed, and not with a feather.

Levush: Some say that one should write it with a reed, and not with a feather, for it does not write, rather, it engraves. We require writing.

Taz (8): Mahari Margoliyos says in Seder Gitin that one should not write with an iron quill, for this is like engraving. Even though one may carve out the letters themselves (i.e. but not to carve the interiors), it is better not to engrave at all.

Mas'as Binyamin (99): There is no difference between written and printed Seforim. A Get Shichrur (engraved) on a tablet is Kosher. The Kohen Gadol's Tzitz and the Luchos were engraved. The Torah often calls these 'Kesivah'. This shows that writing and engraving are the same. The Gemara disqualifies engraving Tuchos. Printing is like standard writing, which is not engraving. It is sticking ink to the page. A press is no different than a quill. However, perhaps printing is different, for an entire page is written at once. Perhaps every letter requires its own Ko'ach (force) and Kedushah!

Taz (8): Some say that printed Seforim do not have Kedushah like written Seforim. I disagree. Even if it is considered engraving, it is Kosher for a Get if he engraves the letters themselves, even though it says "he will write for her", and not 'he will engrave.' Another proof is from Sotah 48b. If printing were called engraving, what forced the Gemara to say that Avnei Efod require the Shamir, which is scarce? Perhaps it is through our printing, and with ink! Rather, our printing is writing, and not engraving. Mas'as Binyamin says that our printing is Kodesh like writing. He learns from the Efod that also engraving gets Kedushah. I say that it is only writing. What is the difference if one presses a pen on paper, or presses paper on lead letters? One should not print a Get, for it slightly resembles engraving, but one who does not honor printed Seforim will be punished for this.

Chavos Ya'ir (184): Printed Seforim have Kedushah, like the Taz said. However, his proof is invalid. They did not know about printing 300 years ago! The Nefesh of a Stam Yisrael clings to Hash-m, and the Kedushah descends to what he writes.

Pischei Teshuvah (20): The Taz connotes that l'Chatchilah, one may print Seforim. Bnei Yonah says that if even one letter was printed, it is Pasul, even if it is printed on parchment.

Levush (284:1): It seems that people are not Yotzei hearing the Haftorah from a printed Chumash, since they are not written according to laws of writing a Sefer Torah or Megilah.

Magen Avraham (Reish 284): The Heter to write a Sefer just of the Haftoros (Gitin 60a) was when Seforim were expensive and the Tzibur could not afford a set of Nevi'im. Nowadays, we can print Seforim cheaply, and this is considered proper writing, therefore, one may not write just the Haftoros. Shiltei ha'Giborim (Shabbos 43a DH Kol) says that only a Sefer Torah or Megilah must be written with ink.

Magen Avraham (32:26): Writing Tuchos is Pasul (for Tefilin), because he does not do an action in the letters themselves. It does not help to pass the quill over the letter.

Rema (EH 125:4): Some say that l'Chatchilah one should be stringent not to write a Get with an iron pen, lest he come to engrave.

Beis Shmuel (4): Even though engraving the letters is Kosher, we are concerned lest he come to engrave the insides of the letters.

Tevu'as Shor (3:4): If one threw a rock and it hit a knife and the knife slaughtered, it is Pasul due to a Safek. This is Ko'ach Kocho, and perhaps it is not like Kocho. Regarding Galus, we hold that it is not like Kocho (Makos 8a). In truth, the Rambam connotes that he is exempt due to Ones, i.e. even if Ko'ach Kocho is like Kocho. Regarding damages, Ko'ach Kocho is like Kocho (Bava Kama 19a)! In any case, since the Gemara distinguishes between Kocho and Ko'ach Kocho, we cannot be lenient about Shechitah.

Chelkas Yo'av (EH 105): Perhaps a Get written through a typewriter is Pasul mid'Oraisa, and it does not help even in pressed circumstances in a case of Igun (she will be unable to remarry). Even regarding Shechitah, which is more lenient than writing a Get, e.g. it does not require intent, Tevu'as Shor says that it is not like Kocho. Even regarding damages, Tosfos and the Rambam hold that it is not like Kocho. The Shulchan Aruch (CM 390:5) says 'one opinion (the Rosh) holds that Ko'ach Kocho is like Kocho. Regarding Yayin Nesech, Tosfos and the Rosh (Avodah Zarah 60a) and YD 125:2 hold that pushing a beam onto a board is Ko'ach Kocho. The same applies whenever one pushes one thing, and it pushes another. This is unlike a wheel with a knife attached (if one spins it and it slaughters, this is Kosher). When one writes on a typewriter (not all typewriters are the same), he presses a key at the end of a metal stick, and this makes another stick move... until the stick with the letter strickes the paper. Even though the sticks are connected, they are not one solid matter. There is a small space between them. This is Pasul for Shechitah, and all the more so for Get. Maharsham brought from Menachos that shaking a Kli to make the Kometz fall is not considered his action. This supports Tevu'as Shor. The typewriter is not exactly the same, but who can distinguish them? In any case it is a Safek, and it does not help against the Chazakah that she is married. We must say that all the Poskim who permit printed Gitin discuss when he struck the paper in a way that is not Ko'ach Kocho. If it is Ko'ach Kocho, we cannot permit even b'Di'eved.