Great care must be taken in the writing of the letters, so that there will be no change, even minor, in the shape of even a single letter, and so that one letter will not resemble another. All of the letters, words, and passages of the Tefillin and the Mezuzah must be written in exact order, that is, in the order they appear in the Torah. This requirement of order of writing does not apply to Torah scrolls and to Megillot (of course, the passages must appear in the scrolls in the correct order).
he shape of even a single letter, and so that one letter will not resemble another. All of the letters, words, and passages of the Tefillin and the Mezuzah must be written in exact order, that is, in the order they appear in the Torah. This requirement of order of writing does not apply to Torah scrolls and to Megillot (of course, the passages must appear in the scrolls in the correct order).
The "Crowning" of the Letters
The letters of the Hebrew alphabet as written by a scribe are divided into three categories, according to the number of tagim ("crowns") on each letter:
Group 1 Each of these letters must have three crowns.
Group 1 Each letter in this group has only a single crown.
Group 1 The letters in this group (that, interestingly, spell out the words melekhet sofer - the scribe`s work; the letters of the other groups also are arranged in acrostics) have no crowns
