What does the expression 'everything in Linux is considered a file' mean and how does it relate to system architecture?

The expression "everything in Linux is considered a file" means that almost all resources and devices in the system are represented through the filesystem.

This includes:

• Regular files and directories
• Input/output devices (e.g., /dev/sda for disk, /dev/tty for terminal)
• Network sockets
• Processes (via /proc)

This approach simplifies interaction with various resources — they are accessed using unified system calls (open, read, write, close).

Relation to architecture:

• Provides a unified interface for interacting with hardware and system resources.
• Simplifies the development of programs and drivers.
• Enhances modularity and extensibility of the system.

For example, to read data from a device, it is enough to open the corresponding file and read from it, just like a regular file.