Real-world uses of Algebraic Structures I am a Computer science student, and in discrete mathematics, I am learning about algebraic structures. In that I am having concepts like Group,semi-Groups etc...    
Previously I studied Graphs. I can see a excellent real world application for that. I strongly believe in future I can use many of that in my Coding Algorithms related to Graphics.
Could someone tell me real-world application for algebraic structures too...

Here's one place to start. The Unreasonable Effectiveness of Number Theory contains the following interesting surveys. Their references should provide good entry points to related literature.
• M. R. Schroeder -- The unreasonable effectiveness of number theory in physics, communication, and music  
• G. E. Andrews -- The reasonable and unreasonable effectiveness of number theory in statistical mechanics  
• J. C. Lagarias -- Number theory and dynamical systems  
• G. Marsaglia -- The mathematics of random number generators  
• V. Pless -- Cyclotomy and cyclic codes  
• M. D. McIlroy -- Number theory in computer graphics
