Why do c++ programmers use != instead of <

Question

In c++ primer, pg 95 the author says that c++ programmers tend to use != in preference of < when writing loops.

for (vector::size_type i = 0;          


        

Answer 1

Because, in general, not all iterators support the "<" operation. See the manual for operation supported by each iterator type. Only random access iterators (of which, simple pointers are a subset) support inequality comparisons (< and >) between iterators