In today's digital world, Computer Science has become an important subject for everyone to learn about. The knowledge and Computational Thinking skills associated with it are now crucial to developing innovative digital technology, understanding modern society, and qualifications in this area are highly sought after.
This is where Computer Science comes in; many areas of Computer Science are employed to make the system work well, and most of them are illustrated through Unplugged. How could you search billions of items in a fraction of a second (Searching Algorithms)? How do you make sure that it's easy to use (Human-Computer Interaction)? We need to keep it secure - users don't want other people to know what they are searching for, and the search engine doesn't want commercial interests to manipulate search ranking (Computer Security and Encryption)? Search engines generally predict what you are about to search for (Artificial Intelligence). It needs to be reliable - a small mistake from one of the thousands of programmers at a search engine company shouldn't prevent the site working (Software Engineering). It needs to scale well - if it becomes 10 times as popular, you don't want it to need 100 times the computing resources (Algorithms). The relevance of a search generally depends on the relationships between web sites - you need a map showing which sites are linked to which other ones (Graphs).
The areas above cover much of what the subject of Computer Science is about. Programming is just a tool for implementing ideas (well, it's a very powerful tool, and requires considerable skill to use well). But programming on its own isn't enough to create software that people love to use, and Computer Science is the area that gives programmers the inside knowledge to make their software fast, efficient, reliable, secure, usable, intelligent, scalable, and even delightful!