Eijkhout, Chow, and van de Geijn's "Introduction to High-Performance Scientific Computing, Chapter 2: Parallel Computer Architecture"
Read section 2.8 of Chapter 2 on pages 79 and 80 to learn about GPU computing. GPU stands for Graphics Processing Unit. These are of interest because of the increase in the amount of graphics data handled by popular laptops and desktop computers. Furthermore, it turns out that since a GPU does primarily arithmetic computations, the architecture of a GPU is applicable to other types of applications that involve arithmetic on large amounts of data.
Read section 2.10 of Chapter 2 on pages 82 and 83 to learn about distributed, grid, and cloud computing. These are configurations of multiple computers for increasing performance and/or decreasing cost for high volume database access, sharing of resources, or accessing remote computer resources, respectively.