Markdown Inlines Combined

Combining inline Markdown elements:

With asterisks:

Emphasis
Strong
Emphatic strong
*** not Emphatic strong (leading space)***
***Emphatic strong (trailing space) ***
* spaced markers * (a leading space)
** spaced markers **

With underscores:

Emphasis
Strong
Emphatic strong

Mixed underscores and asterisks - must be properly nested:

Emphatic strong
Emphatic strong

Overlapping (not nested) demarcation:

**emphatic strong**
*strong emphasis*
~~emphatic strikethrough~~
**striken strong**

With tildes:

Strikethrough
Emphatic strikethrough
Stricken emphasis
Strong stricken emphasis

url text
url text emphasized
url text embedded
url text strong
url text emphasized, strong embedded
url text stricken

Code spans may be embedded in other inlines, but not vice versa.

code span emphatic
code span strong
code span stricken
url text embedded code in url

But not

*code span* emphatic
**code span** strong
~~code span~~ stricken
[url text](@) embedded code in url

Math (where enabled) ignores emphasis:

$y=x_1+x_2$
$y=x_1+x_2$ emphatic
$y=x_1+x_2$ striken
$y=x_1+x_2$ as url text

Code spans and math can’t mix.