Off-shell

Babel

en	This user can contribute with a pidgin level of English.

de	Dieser Benutzer hat tiefergelegte Deutschkenntnisse.

ru	Этот участник владеет русским языком на печальном уровне.

!fr	Cet utilisateur est honteux de ne pas parler français.

ph	This user can contribute with a basic level of Physics.

pe	This user can contribute with a basic level of Perl.

Formerly, they were known as the wise men. Nowadays, they are called the experts.

Wikipedia pretents to explain to a kindergarten child what it means to be on shell and off shell.