The dmesg command can be used to view the boot messages printed by Linux kernel. The Linux kernel maintains a ring buffer (default size 16KB) to hold boot-time messages printed using printk() function call in kernel code. The dmesg command can be used to control the ring buffer as well.

[neo@techpulp ~]$ dmesg
Linux version 2.6.23.15-137.fc8 (mockbuild@xenbuilder2.fedora.redhat.com) (gcc version 4.1.2 20070925 (Red Hat 4.1.2-33)) #1 SMP Sun Feb 10 17:48:34 EST 2008
BIOS-provided physical RAM map:
BIOS-e820: 0000000000000000 - 000000000009dc00 (usable)
BIOS-e820: 000000000009dc00 - 00000000000a0000 (reserved)
BIOS-e820: 00000000000d2000 - 0000000000100000 (reserved)
BIOS-e820: 0000000000100000 - 000000007bf10000 (usable)
BIOS-e820: 000000007bf10000 - 000000007bf19000 (ACPI data)
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