With that logic this echoes "echo". Question about echo!

echo `echo `

doesn't echoes anything. And it's logic. But

echo `echo `echo ` `

does echoes "echo". What's the logic of it? the `echo `echo ` inside of the whole (first) echo, echoes nothing, so the first echo have to echo nothing but echoes "echo"

(too much echoing :P):o

That is because backticks have to be escaped if you nest them:

echo `echo \`echo \` `

You do not need to with the more modern $(..) command substitution construct:

 echo $(echo $(echo))

Thx, it seems interesting