main memory -> RAM
database → HDD
data warehouse
heap : dynamic
stack : till program ends
-
time complexity : how time grows with size of input O -> 'order of'
slower step decides the order
O(1) -> constant time irrespective of input
O(n) -> most impactful term is of nth order or linear
Big O :
A function f(n) is said to be O(g(n)) iff there exists a constant c and n_o such that 0<=f(n)<=cg(n) for n>=n_o
