LILO and GRUB are boot loaders used in Linux systems.
A boot loader is a small program that loads the operating system kernel into memory when the computer starts.

1️⃣ LILO

LILO stands for Linux Loader.

🔹 Features:

• One of the earliest Linux boot loaders.
• Loads Linux kernel from hard disk.
• Supports dual boot (Linux + other OS).
• Configuration stored in /etc/lilo.conf.

🔹 Limitation:

• After changing configuration, you must run the lilo command again.
• Does not understand filesystems (uses fixed disk locations).
• No interactive command interface.

👉 LILO is now mostly outdated.

2️⃣ GRUB

GNU GRUB stands for GRand Unified Bootloader.

🔹 Features:

• Modern and widely used Linux boot loader.
• Supports multiple operating systems.
• Has interactive command line interface.
• Automatically detects installed OS.
• Understands filesystems.
• Configuration file: /boot/grub/grub.cfg.

🔹 Advantages over LILO:

• No need to reinstall after every change.
• More flexible and powerful.
• Supports network booting.

👉 GRUB replaced LILO in most modern Linux distributions.

🔍 Difference Between LILO and GRUB

🎯 Simple Definition (Exam Ready)

• LILO is an older Linux boot loader used to load the Linux kernel.
• GRUB is a modern boot loader that supports multiple operating systems and advanced features.