"firstItem" is a variable that stores the value at the first position (index 0) of an array. It serves as temporary storage before shifting all other elements in the array by one position.
Related terms
Variable: A named container or storage location used to hold values that can change during program execution.
Value: The content/data assigned to a variable. In this case, it refers to what's stored at the first position in the array.
Shift: To move or change the position of elements/values within a data structure.