What Flat panel is
A type of computer monitor that is very thin and flat-looking. In fact, it almost looks like it's just a screen (there's no bulky hardware behind it). It uses an LCD to display information, and there is less glare and radiation. It is not the same as a flat screen.
The meaning of Server farm
A group of networked servers that are housed in one location in order to streamline internal processes, distributing the workload between the individual components. In other words, a server farm expedites computing processes by harnessing the power of multiple servers. The farms rely on load-balancing software that tracks demand for processing power from different machines, prioritizes the tasks, and schedules and reschedules them depending on the priority and demand that users put on the network. When one server in the farm fails, another can step in as a backup.
Combining servers and processing power into a single entity has been relatively common for many years in research and academic institutions. Today, more and more companies are utilizing server farms to handle the enormous amount of computerized tasks and services they require.