[ditaa,asciidoctor-diagram-ditaa]
....
                   +-------------+
                   | Asciidoctor |-------+
                   |   diagram   |       |
                   +-------------+       | PNG out
                       ^                 |
                       | ditaa in        |
                       |                 v
 +--------+   +--------+----+    /---------------\
 |        |---+ Asciidoctor +--->|               |
 |  Text  |   +-------------+    |   Beautiful   |
 |Document|   |   !magic!   |    |    Output     |
 |     {d}|   |             |    |               |
 +---+----+   +-------------+    \---------------/
     :                                   ^
     |          Lots of work             |
     +-----------------------------------+
....

[plantuml,auth-protocol-plantuml]
....
skinparam roundcorner 20
skinparam sequence {
  BackgroundColor PaleGreen
  ArrowColor SeaGreen
  BorderColor SpringGreen
}

actor Bob #blue
Alice -> Bob: Authentication Request
Bob --> Alice: Authentication Response

Alice -> Bob: Another authentication Request
Alice <-- Bob: another authentication Response
....