Update tables_symbols_math.adoc

Signed-off-by: Kersten Richter <[email protected]>

src/tables_symbols_math.adoc

@@ -1,7 +1,27 @@
 [[tables_symbols_math]]
 == Tables, symbols, and math
 
-Asciidoc makes standard tables easy and also supports the creation of complex tables.
+Asciidoc makes standard tables easy and also supports the creation of complex tables. As a general rule, do not present new information in tables
+
+=== Table rules
+
+==== Table formatting
+
+- Align tables to center with the options `float="center"` and `align="center"`.
+- Use table header coding to indicate a header. Don't use a different font, color, or any background indication.
+- Sort rows in either a logical order or by alphabetizing the rows and columns.
+- If your table is long or complicated, consider creating multiple tables. If you do choose to create a complicated table, make sure that 
+- Use table captions to describe your table contents. Captions appear after the table and are controlled by the theme.
+- If you use footnotes in your table, make sure they appear immediately after the table.
+- Remember that tables can be hard for screen readers to parse. If your table is complex, be sure that the contents are described in the text. 
+
+
+=== Column header formating
+
+- Use sentence case.
+- Write concise headings and omit articles (a, an, the).
+- Don't end with punctuation, including a period, an ellipsis, or a colon.
+- Use table headings for the first column and the first row only.
 
 [WARNING]
 ====
@@ -79,7 +99,7 @@ Either table renders with table headers.
 |===
 
 
-=== Asciidoc tables from CSV data
+=== Asciidoc tables from CSV data.
 
 AsciiDoc tables can also be created directly from CSV data. Set the format block attribute to `csv` and insert the data inside the block delimiters directly:
 
@@ -102,13 +122,8 @@ Baauer,Harlem Shake,Hip Hop
 The Lumineers,Ho Hey,Folk Rock
 |===
 
-=== Other table formatting options
 
-There are numerous formatting options available. While some of the property settings are cryptic, they can be quite useful. There are numerous examples available at https://asciidoc.org/newtables.html. 
-
-==== Table column spans
-
-Here one example of what can be done with spans alignment in tables from that page:
+There are numerous formatting options available. While some of the property settings are cryptic, they can be quite useful. There are numerous examples available at https://asciidoc.org/newtables.html. Here one example of what can be done with spans alignment in tables from that page:
 
 [source,adoc]
 ----
@@ -131,9 +146,6 @@ Which renders as follows:
 |9 2+>|10
 |============================
 
-
-==== Numbered encoding table
-
 The following example is code for a numbered encoding table with link target.
 
 NOTE: Annotations have been added to the code to illustrate their use.
@@ -319,4 +331,3 @@ In some cases, you might want to make use of unicode characters. Keep in mind th
 For updates to asciidoctor-pdf, see https://github.com/asciidoctor/asciidoctor-pdf.
 
 
-