General UNIX interview questions

1. What are the main differences between Apache 1.x and 2.x?
2. What does the “route” command do?
3. What are the read/write/execute bits on a directory mean?
4. What does iostat do?
5. what does vmstat do?
6. What does netstat do?
7. What is the most graceful way to bring a system into single user mode?
8. How do you determine disk usage?
9. What is AWK?
10. What is SED?
11. What is the difference between binaries in /bin, and /usr/bin?
12. What is a dynamically linked file?
13. What is a statically linked file?