The 
                  aside element represents information supplementary to the main text and/or narrative flow. 
                  
               
               The 
                  Block variant is an adaptation for use with asides that contain unstructured content.
                  
               
                An aside typically floats separate from the main text, often in a boxed or shaded region. 
                The 
                  
                     role
                      attribute optionally expresses the semantic nature of the aside. 
                  
               
             
            Usage Example
<aside role="sidebar">
    <hd>Quail Island</hd>
    <p>Quail Island is located …</p>
    <p>Darwin's travels would have brought him to the island …</p>
</aside>
    Allowed parents
            address, 
               annotation, 
               m:annotation-xml, 
               aside (block variant), 
               aside (toc variant), 
               backcover, 
               bibliography, 
               block, 
               caption, 
               description, 
               entry (bibliography variant), 
               entry (glossary variant), 
               flaps, 
               frontcover, 
               glossary, 
               index, 
               item, 
               d:longdesc, 
               note (block variant), 
               note (phrase variant), 
               object, 
               sel:otherwise, 
               quote, 
               section (section variant), 
               section (index variant), 
               section (bibliography variant), 
               section (glossary variant), 
               d:simplifiedLanguageDescription, 
               d:summary, 
               td, 
               th, 
               d:tour and 
               sel:when
               
            
            Allowed children
            This element may contain text.
            
            This element may contain the following children: abbr, 
               address (block variant), 
               address (phrase variant), 
               annoref, 
               annotation (block variant), 
               annotation (phrase variant), 
               aside, 
               block, 
               ssml:break, 
               caption, 
               char, 
               citation (block variant), 
               citation (phrase variant), 
               code (block variant), 
               code (phrase variant), 
               d, 
               definition, 
               description, 
               d:description, 
               emph (text variant), 
               emph (phrase variant), 
               expansion, 
               xforms:group, 
               hd, 
               xforms:input, 
               rend:linebreak, 
               list, 
               ln, 
               m:math, 
               name, 
               note (block variant), 
               note (phrase variant), 
               noteref, 
               num, 
               object (block variant), 
               object (text variant), 
               object (phrase variant), 
               p, 
               pagebreak, 
               ssml:phoneme (text variant), 
               ssml:phoneme (phrase variant), 
               ssml:prosody (text variant), 
               ssml:prosody (phrase variant), 
               quote (block variant), 
               quote (phrase variant), 
               xforms:range, 
               ref, 
               xforms:repeat, 
               its:ruby, 
               s, 
               ssml:say-as (text variant), 
               ssml:say-as (phrase variant), 
               xforms:secret, 
               sel:select (Block variant), 
               sel:select (Phrase variant), 
               xforms:select, 
               xforms:select1, 
               span (text variant), 
               span (phrase variant), 
               sub, 
               ssml:sub (text variant), 
               ssml:sub (phrase variant), 
               sup, 
               table, 
               term, 
               xforms:textarea, 
               time, 
               ssml:token (text variant), 
               ssml:token (phrase variant), 
               transition, 
               verse and 
               w
               
            
            Content model and additional requirements
            
               optional attributes: 
@about, 
                  
@by, 
                  
@class, 
                  
@content, 
                  
@datatype, 
                  
@desc, 
                  
@its:dir, 
                  
@its:translate, 
                  
@property, 
                  
@rel, 
                  
@resource, 
                  
@rev, 
                  
@role, 
                  
@sel:selid, 
                  
@ssml:onlangfailure, 
                  
@typeof, 
                  
@xml:base, 
                  
@xml:id, 
                  
@xml:lang and 
                  
@xml:space 
               a choice of
                  
                  either 
one or more of 
                     
                     any of the 24 elements: 
address, 
annotation, 
aside, 
block, 
caption, 
citation, 
code, 
d:description, 
description, 
hd, 
list, 
m:math, 
note, 
object, 
p, 
pagebreak, 
quote, 
sel:select, 
ssml:break, 
table, 
transition, 
verse, 
xforms:group and 
xforms:repeat 
                     
                   
                  
                  or 
one or more of 
                     
                     a choice of either one of the 53 elements: 
abbr, 
address, 
annoref, 
annotation, 
char, 
citation, 
code, 
d, 
definition, 
emph, 
emph, 
expansion, 
its:ruby, 
ln, 
m:math, 
name, 
note, 
noteref, 
num, 
object, 
object, 
pagebreak, 
quote, 
ref, 
rend:linebreak, 
s, 
sel:select, 
span, 
span, 
ssml:break, 
ssml:break, 
ssml:phoneme, 
ssml:phoneme, 
ssml:prosody, 
ssml:prosody, 
ssml:say-as, 
ssml:say-as, 
ssml:sub, 
ssml:sub, 
ssml:token, 
ssml:token, 
sub, 
sup, 
term, 
time, 
w, 
w, 
xforms:input, 
xforms:range, 
xforms:secret, 
xforms:select, 
xforms:select1 or 
xforms:textarea 
                        or text
end of choice 
                     
                   
                  end of choice 
               Note that in addition to restrictions presented in the content model  above, 
                  					use of this element must also respect the following requirement:
                  
                     - The 
                        
aside element must neither be empty nor contain only whitespace.
                        
                      
                  
                  Such requirements take precedence over any conflicting statements in the
                     						content model or in the lists above of allowed children and parents.
                  
                
             
            Variants
            This element exists in 3 variants. The other 2  variants are:
            
            Namespace
            http://www.daisy.org/ns/z3998/authoring/