The Help has a good section on this subject:
Tabs and margins
As e-mail becomes more like word processing, with features like tables, styles, pictures and so on, so the end user expects that the e-mail program will behave more like a word processor. In traditional e-mail, margins and tab settings were always calculated in characters, but in modern systems with proportionally-spaced typefaces, it makes more sense to use absolute measures for these settings. Accordingly, in normal operation, Pegasus Mail lets you specify the right margin and tab settings for your messages using either inches or millimetres. If you have checked Disable all text styling options (see above) then Pegasus Mail, will behave like an old-fashioned teletype mailer and will use characters as the measurements for these settings. Which of these operating modes best suits you is a matter of personal taste.
Message width This setting controls how wide the column of text you type in your message should be. The default setting is 145mm or 5.71 inches, based on a typeface of Arial 10 point. This will result in a column of text approximately 76 characters wide, which should be readable by anyone. If you increase the size of your typeface, you may also need to increase the message width, since otherwise your lines will become shorter and shorter. Similarly, if you use a smaller typeface, you should make the message width narrower to keep the lines within a reasonable length. Experiment with these settings until you find a message width that youfind comfortable and which produces messages your correspondents have no trouble reading. As a general rule of thumb, you should choose settings that result in the lines in your message being between 70 and 80 characters long.
Tab width Controls the approximate distance between tabs in the message editor. The default value is 12mm, or half an inch.
Units Allows you to select whether measurements should be expressed in metric (millimetres) or imperial (inches). Pegasus Mail remembers this setting from session to session, so you only have to select it once.
Right margin for Ctrl+J reformatting command Sometimes the text in your messages can become quite unruly, especially when you are quoting sections from an original message in a reply. Pegasus Mail incorporates a Reformat text command, available by pressing Ctrl+J in the editor. This command tidies up the current paragraph, and can work with either normal text or quoted text. Because of the nature of this command, it always works using characters as a unit of measure, irrespective of your current margins.You can set the right margin used in the Ctrl+J command by entering it here.
Current RFC5322 recommends setting your right margin at 78 chars or less and I would suggest you set the ctrl+j function value at 78 chars also. I keep my Editor set to 74 chars to allow for at least one level of quoted text in replies. Once you set the value and have saved it then you can uncheck the item in Message Formatting section to allow use of HTML or multipart/alternative type mail. With the item checked your email would all be normal plain text messages in older versions WinPMail series like v3.x, v2.x and v1x and MSDos PMail was. As you toogle the setting in Message formatting section you will see the shown values change to match the converted measurements to match the amount set in the normal chars count method.
<p>The Help has a good section on this subject:</p><p>Tabs and margins
As e-mail becomes more like word processing, with features like tables, styles, pictures and so on, so the end user expects that the e-mail program will behave more like a word processor. In traditional e-mail, margins and tab settings were always calculated in characters, but in modern systems with proportionally-spaced typefaces, it makes more sense to use absolute measures for these settings. Accordingly, in normal operation, Pegasus Mail lets you specify the right margin and tab settings for your messages using either inches or millimetres. If you have checked Disable all text styling options (see above) then Pegasus Mail, will behave like an old-fashioned teletype mailer and will use characters as the measurements for these settings. Which of these operating modes best suits you is a matter of personal taste.
Message width&nbsp; This setting controls how wide the column of text you type in your message should be. The default setting is 145mm or 5.71 inches, based on a typeface of Arial 10 point. This will result in a column of text approximately 76 characters wide, which should be readable by anyone. If you increase the size of your typeface, you may also need to increase the message width, since otherwise your lines will become shorter and shorter. Similarly, if you use a smaller typeface, you should make the message width narrower to keep the lines within a reasonable length. Experiment with these settings until you find a message width that youfind comfortable and which produces messages your correspondents have no trouble reading. As a general rule of thumb, you should choose settings that result in the lines in your message being between 70 and 80 characters long.
Tab width&nbsp; Controls the approximate distance between tabs in the message editor. The default value is 12mm, or half an inch.
Units&nbsp; Allows you to select whether measurements should be expressed in metric (millimetres) or imperial (inches). Pegasus Mail remembers this setting from session to session, so you only have to select it once.
Right margin for Ctrl+J reformatting command&nbsp; Sometimes the text in your messages can become quite unruly, especially when you are quoting sections from an original message in a reply. Pegasus Mail incorporates a Reformat text command, available by pressing Ctrl+J in the editor. This command tidies up the current paragraph, and can work with either normal text or quoted text. Because of the nature of this command, it always works using characters as a unit of measure, irrespective of your current margins.You can set the right margin used in the Ctrl+J command by entering it here.</p><p>&nbsp;</p><p>Current RFC5322 recommends setting your right margin at 78 chars or less and I would suggest you set the ctrl+j function value at 78 chars also. I keep my Editor set to 74 chars to allow for at least one level of quoted text in replies. Once you set the value and have saved it then&nbsp; you can uncheck the item in Message Formatting section to allow use of HTML or multipart/alternative type mail. With the item checked your email would all be normal plain text messages in older versions WinPMail series like v3.x, v2.x and v1x and MSDos PMail was. As you toogle the setting in Message formatting section you will see the shown values change to match the converted measurements to match the amount set in the normal chars count method.
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