the.com/pointers
a variable whose entire job is knowing where another variable lives.
means a pointer is a value that stores a memory address instead of data, letting code find and manipulate something without copying it.
from formalized in the 1960s with bcpl and cemented by c in the early 1970s, when dennis ritchie needed a fast way to reference memory directly instead of dragging whole data structures around.
null pointerpoints to nothing, crashes programs for decades.
invented byharold lawson, arguably, in 1964.
double meaningpointer to a pointer is legal and common.
famous apologytony hoare called null his billion-dollar mistake.