This chapter discusses the first CPU parallel program, imflipP.c. It explains the concepts that are the backbone of a parallel program. Each thread executes its assigned task and returns. The entire purpose of creating more than one thread was to execute things faster. This, by definition, means that the more threads people create, the more task splitting they have to do, and the more data splitting they have to do. A Bitmap (BMP) file is an uncompressed image file. This means that by knowing the size of the image, people can easily determine the size of the file that the image is stored in. The chapter focuses on the concept of compression. A BMP file stores "raw" image pixels without compressing them; because compression is not performed, no additional processing is necessary before each pixel is stored in a BMP file.