[operation] remove first element [common name(s)] pop [Ada] Delete_First [Java] pollFirst [Perl] shift [PHP] array_shift [Python] popleft [Ruby] shift [JavaScript] shift [C++] 
pop_front
p u s h _ b a c k
p u s h _ f r o n t
p o p _ b a c k
p o p _ f r o n t
b a c k
f r o n t