Typography

1. The four most im­por­tant ty­po­graphic choices you can make in any doc­u­ment are point size, line spac­ing, line length, and font; be­cause these choices de­ter­mine how the body text looks.
2. Point size should be 10–12 points in printed doc­u­ments, 15-25 pix­els on the internet or blog.
3. Line spac­ing should be around 120–145% of the point size
4. The av­er­age line length should be around 45–90 char­ac­ters (which in­clud­es spaces).
5. The eas­i­est, most vis­i­ble im­prove­ment you can make to the ty­pog­ra­phy is to use a profes­sional font, like those found in font rec­om­men­da­tions. Avoid goofy fonts, monospaced fonts, and sys­tem fonts, es­pes­cially times new ro­man and Arial 
6. Use curly quo­ta­tion marks, not straight ones.
7. Put only one space be­tween sen­tences.
8. Don’t use mul­ti­ple word spaces or other white-space char­ac­ters in a row. 
9. Never use un­der­lin­ing un­less it’s a hyperlink. 
10. Use cen­tered text sparingly. 
11. Use bold or italic as lit­tle as possible. 
12. all caps are fine for less than one line of text. 
13. If you don’t have real small caps, don’t use them at all.
14. Use 5–12% ex­tra let­terspac­ing with all caps and small caps. 
15. Use first-line in­dents that are one to four times the point size of the text, or use 4–10 points of space be­tween para­graphs. But don’t use both. 
16. If you use jus­ti­fied text, also turn on hy­phen­ation. 
17. Don’t con­fuse hy­phens and dashes, and don’t use mul­ti­ple hy­phens as a dash. 
18. Use am­per­sands spar­ingly, un­less in­cluded in a proper name.
19. In a doc­u­ment longer than three pages, one ex­cla­ma­tion point is plenty. 
20. Use trademark and copy­right sym­bols—not al­pha­beticapproximations.
21. Put a non­break­ing space af­ter para­graph and sec­tion marks.
22. Make el­lipses us­ing the proper char­ac­ter, not pe­ri­ods and spaces.
23. Make sure apos­tro­phes point downward.
24. Make sure foot and inch marks are straight, not curly.