Virtual Machines vs LXC vs Docker: What’s the Real Difference?

Virtual machines provide complete hardware emulation with strong isolation but higher overhead, making them ideal for different guest OSes and strict security requirements. LXC containers share the host kernel while isolating userland, offering VM-like behavior with better performance and density for Linux-only workloads. Docker containers also share the kernel but focus on single applications with immutable images, solving dependency conflicts through portability at the cost of trusting external maintainers. Each approach trades off isolation, performance, density, and maintenance responsibility differently.