When the computer is powered up, after the initial hardware scan and gathering, the BIOS then checks which device contains the boot information. This could be a floppy disk, CD-ROM, or typically, the primary hard drive. The first sector (bootsector) is read. The small program in this area reads a partition table that is kept at the end of the sector. This table has all of the hard drives, their partitions, and their purpose, listed. The one it looks for, specifically, is the one designated as the boot partition. Then, this little program turns over control to another program, called the bootloader, loading it from that boot partition and subsequently running it.
The Operating System (OS) is the software that pulls together all of the hardware components, processors, disks, memory, etc., into a cohesive interface for all users and programs to use. The kernel is the name for the core of the operating system: the program that handles all the software-components controlling the hardware.
Things that the kernel implements are considered to be in kernel space. Everything else, outside of the kernel, is considered user space , and is where software that uses the kernel’s interface runs (managing files, graphical interface, games, word processing, etc).
portscan is a simple port scanner for random IPs or specified IP ranges. Logs the open ports to a separate text file.