Restrict keyword in C

The restrict keyword is a type qualifier for pointers. It is part of the C99 standard. Second link is sufficient explanation to this keyword.

How to use the restrict qualifier in C [developers.sun.com]

Demystifying restrict keyword [cellperformance.beyond3d.com]

Memory Optimization [research.scea.com]
The presentation to this topic.

Keyword volatile

Volatile is cv qualifier. Even though Dan Saks has already described in few articles volatile keyword as a promise, still there's more to find out !

Here's more to this topic:

Introduction to the Volatile Keyword [eetimes.com]
Basics explained as a usage by Nogel Jones.

What does volatile mean [blog.regehr.org]
I suggest reading this one which explains volatile with code examples.

Volatiles Are Miscompiled [http://www.cs.utah.edu/~regehr]

Secret life of volatile [codingrelic.geekhold.com]