Use the correct characters

"(c)" is not an appropriate replacement for “©”
There are many special characters that are rarely done correctly online. Because the web and HTML were generally limited to ASCII and browsers were not quick to adopt better character support we grew used to accepting many substitutes for real typographical symbols. With the advent of self-publishing software like PageMaker, this problem has even bled into print media. This is not a big deal in most settings but for real design or printing it’s important to get it right.

This ' is not an apostrophe and this " is not a quote mark anymore than (r) is a ®. “Real quotes slant like so,” even in «French.» Use the right symbols. Anything less is bad design grammar.

A subtle example that other typesetters will notice is the difference between … and ... The first is a real ellipsis. The second is dot, dot, dot. The first looks better in layout and shows your professionalism.

For web text layout it’s difficult to do these things and not critical to get right. The pages on this site run through a Perl script to correct the quotes and apostrophes in regular cases. In design work, getting this wrong makes a design appear amateurish, e.g.:

"Won't--" in place of “Won’t–”

How to do it right with HTML
There is a good list of the correct character codes at the W3Schools. In my experience browser support seems to favor the number encodings, i.e. ¢ is probably a better choice than ¢ to get ¢. It’s important to match the character set you choose to the DOCTYPE of your page. An excellent site to see the many ways a single character can be had in differing character sets is fileformat.info.

A parting caveat · Some older browsers support neither, and international character sets (foreign users) may also have trouble rendering anything besides ASCII. So using these tricks can result in your pages looking worse for a small percentage of users (almost certainly under 1%).

Layout mistakes

French spacing · French spacing is the placing of two spaces at the end of a sentence to separate it from the next. Bizarrely, there are still those who maintain that it’s correct to do so. Fortunately, none of them works in publishing houses or print shops. The punctuation and the following capital letter are already redundant separators of sentences. To add another isn’t just overkill, it makes a piece of print look like a highschool paper. You will not find French spacing used by any mainstream book, journal, or web publisher.

Widows and orphans · Widows are single lines of a paragraph at the top or bottom of a column/page. Orphans are single (or even duple) words on the line at the end of a paragraph. They are visually jarring. In HTML widows are generally a non issue; pages are not typically rendered in columns. There isn’t much that can be done about orphans in HTML. To fix them both properly in print you can make micro adjustments to the letter spacing and insert column/page breaks manually.

Because of the effort involved and the fact that many publishers have begun to treat novels and textbooks like periodicals, many don’t bother fixing them anymore. Here is a good article about the issue.

All caps · ALL CAPS MAY LOOK NICE ON THE MARBLE FAÇADE OF A BANK BUT IT IS MORE DIFFICULT TO READ THAN LOWERCASE, ESPECIALLY AT SMALL POINT SIZES, WHICH IS WHY LOWERCASE LETTERS WERE INVENTED TO BEGIN WITH, AND IT’S BAD ONLINE ETIQUETTE BESIDES.

Prefer regular mixed case. Uppercase doesn’t usually convey emphasis, but dullness and confusion.