However, professional proof reading has a different meaning, especially in the printing and publishing industries, as the following paragraphs explain:

Comparison Proof Reading
Technically, professional proof reading involves comparison — the comparison between two versions of the same document — to find errors and mark them so the corrector understands the instruction.

Proof reading then involves a critical comparison of the author's copy and the typesetter's proof to be sure that the live copy (the typeset proof) matches the dead copy (the author's copy) word for word, and letter for letter.

The Proof reader will then write instructions directly on the proof using proof reading marks (the traditional shorthand) telling the person who will be making the corrections what to do about the error(s).

Noncomparison Proof Reading
Proof reading by comparison is not the only way professional proof readers work. Comparison proof reading may not, in fact, be possible in publishing that is fully electronic.

If for example, an author uses a word processing program on a personal computer to write an article and transmits the article by modem to the typesetting firm, the typesetter must first insert codes to translate the material into typeset copy before printing out the typeset document.

Only then is there live copy on paper — hard copy. And although that hard copy might be considered a proof, it still needs to be read without anything to compare it with. Therefore, the proof reading cycle for that copy will start with noncomparison or dry proof reading.

Because the original (dead) copy of the article exist only in the mind of the author, the author is the best person to do this dry reading. From there on, the rest of the proof reading stages — ensuring that all marked corrections are executed properly — should be done by comparing the relevant parts of the hard copy with the typeset proof.

Proof Reading vs Editing
Proof reading is not editing. It is not normally part of the proof reader's job to correct nuances of editorial style, to improve or change wording, or to correct grammar. However, many proof reading jobs contain editorial errors in which case proof readers should not spend more than five minutes an hour on editing work unless specifically authorized to do so.

Traditional proof reading and copy editing (editing for consistency in editorial style) are akin but have three major differences:

1. Different kinds of copy.
   An editor works with only one kind of copy, usually a draft; but a proof reader generally works with two kinds, the dead copy and the live.
2. Different markings.
   An editor writes corrections once only, in the running text; but a proof reader writes in the text and in the margin, making two marks for every correction.
3. Different functions.
   An editor's functions are to clarify the author's intent by correcting and improving a manuscript to conform to good usage and a specified editorial style, and to prepare the manuscript for the next step in the publication process. An editor corrects bad grammar and inconsistencies overlooked by the author.

Duties of the Proof Reader
A proof reader works with the language of type. In comparison reading, a proof reader is expected to mark the proof where if differs from the copy, such as where letters, words, line, and spacing are omitted or duplicated.
In any proof reading, the proof reader is expected to spot the following problems related to the use of type:

• Problems in technical quality.
• Confusing punctuation.
• Non-standard grammar.
• Inconsistent editorial or house style.
• Deviations from specifications.
• Discrepancies such as mixed metaphors.
• Incorrect arithmetic.
• Factual errors.

A Proof Reader's Skills
In addition to broad general knowledge, to proof read well takes specialized knowledge, technical know-how, judgement, vigilance, and a 'typographic eye'. Knowledge of type and language and technical know-how can be learned, and judgement comes with experience. But vigilance (unrelenting watchfulness) is a part of your character, attitude, and general state of physical and emotional health.

The typographic eye is a visual nitpicking ability. You must be able to spot evidence of poor work, such as broken letters, a capital O instead of a zero (O,0), a letter l instead of the figure 1 (l,1), and minute misalignments as well as disparities in space.

How to Proof Read
The following points will help towards a professional approach to proof reading. (Written directly on the print out):

• Write your initials, the date, and the version number on the proof.
• Read and absorb the instructions and specification.
• Be sure you have all the dead and live copy.
• Verify that the live copy follows the instructions and specifications.
• Put the dead copy and the live copy side-by-side on your workspace.
• Use a guide such as a rule to keep your place line by line.
• Compare the two versions minutely.
• Watch the live copy for typographic errors.
• Watch the live copy for typographic faults.
• Watch for misspellings and errors in language (even in the copy).
• If you have the authority to query, do so tactfully.
• Use a standard dictionary to verify spelling.
• Use the standard proof reader's marks.
• Use a coloured pen to mark proofs (never use a pencil).
• After your comparison reading, read the live copy by itself again.

Rules for Proof Reading
To perform simplified proof reading, follow seven basic rules:

1. Mark an error twice — first in the text, then in the margin.

The textual and the marginal marks are almost always different. Textual marks show where to make the correction; marginal marks show what correction to make. Marginal marks also keep the corrector from having to search for marks in the text.

2. Separate marks in the margins with slashes.

Slashes are used to separate the marginal marks when one, two, or more different corrections are to be made in the same line of text matter.

3. Mark in both margins, using the margin nearer the error.

To prevent overcrowded margins, use an imaginary line to divide the type area into right and left halves. You need not be precise about dividing the page, just use both margins as best you can.

4. Mark from left to right.

As an example below shows, mark from left to right where more than one error occurs in a line. Use slashes to separate the marks.

5. Ring instructions and explanations.

A ring around a mark in the margin means that the message in the ring isn't to be set or typed. The ring is very useful. You can tell the corrector exactly what to do; for example:

6. Mark only on material you will not harm.

You need to make proof reading marks directly on the latest version of the material. However, do not mark an original that cannot be replaced. Mark only printer's proofs, photocopies, printouts, or hard copy.

7. Write clearly and mark neatly.

Proof reading fails if your handwriting or your marks will be misread. If anyone has ever complained that your handwriting is hard to read, you must print.

The following points should be remembered when proof reading:

Confusion and Repetition of Marks
Do not confuse textual and marginal marks. No characters or words belong between the lines; only proof reading marks go there. Avoid repeating a marginal mark in the text or placing a marginal mark in the text.

Spacing and Position changes resulting from corrections
Ordinarily, when you mark for deletion or insertion of type, don't try to mark to adjust the spacing after a correction that changes the number of characters in a line. You should leave it to the corrector to adjust spacing and word division.

Neatness
Cross out characters carefully and clearly, including punctuation; the corrector must be unable to mistake what you want. Good handwriting is essential.

Guidelines
In this topic, you are learning the book system of proof reading marks. Another standard system is the guideline system. Guidelines (pathlines, kitestrings) invite confusion, as they create the sort of maze shown below. Do not use them.

Book System

Guideline System