Thread: whats th difference between *ptr and **ptr in a signature..

when i got in my function signature node *ptr it takes the pointer as a parameter.

what happens if its node **ptr

i know that node* is a type of variable in a funtion
it says "take a node type variable called ptr"

but when i do node **ptr
by my logic it says "take a node type variable called *ptr"


i was told that in the node *ptr we cant change the parameter
but int the ** we can

and i cant see how it goes in the memory
whats the difference?