What is the common name for the kernel image file?

The kernel image file is commonly referred to as "vmlinuz." This name indicates that the file is a compressed version of the Linux kernel, where "vmlinux" is the uncompressed kernel image. The "z" at the end of "vmlinuz" signifies that it is a zipped (compressed) file. While "vmlinux" is the bare kernel image file, "vmlinuz" is typically the name used in the boot process.

In a Linux environment, when configuring the bootloader (like GRUB), you'll often point it to "vmlinuz" rather than "vmlinux" because the boot process requires the compressed image for efficiency and size in loading the kernel into memory.

The other options listed—initramfs.img and boot.img—serve different purposes. "initramfs.img" is used to load the initial RAM filesystem during the boot process, while "boot.img" generally refers to a disk image that might contain various boot-related files, including but not limited to the kernel. Thus, "vmlinuz" is the most widely recognized name for the kernel image file due to its direct link to the boot process and its compressed format.