Operating Systems and Networks: What is the difference between TCP and UDP? Explain how DNS works. What is the difference between IPv4 and IPv6? Can you explain the OSI model and each of its layers? What is the role of DHCP in a network? What is a subnet mask, and why is it important? Describe the process of how a device connects to a network. Hardware and Infrastructure: What are RAID levels? Explain the differences. How do you troubleshoot hardware failures? What is the purpose of a network switch, and how does it differ from a router? Explain the difference between a hub and a switch. What are the different types of storage devices used in IT infrastructures? Software and Programming: Which programming languages are you proficient in? Can you explain your experience with each? How do you approach debugging a software issue? What are the differences between a compiled language and an interpreted language? Explain the concept of a version control system (e.g., Git). What is your experience with cloud computing services (e.g., AWS, Azure, GCP)? Security: What are the best practices for securing a network? How would you protect a system from a DDoS attack? What is encryption, and why is it important in IT security? What is two-factor authentication (2FA)? Explain the concept of a firewall and how it works. Databases: What is SQL, and what are its key commands? What is the difference between SQL and NoSQL databases? Explain normalization in database design. How would you approach performance tuning in a database