A server is a high-performance computer that runs specific application software in a network environment to provide shared information resources and various services to online users. Its English name is SERVER. Since a server is a high-performance computer, its composition is similar to that of a personal computer (PC), such as CPU, memory, hard disk, various buses, etc. However, it can provide various shared services (network, web applications, databases, files, printing, etc.) and other high-performance applications. Its high performance is mainly reflected in high-speed computing power, long-term reliable operation, and strong external data throughput capability, which makes it the hub of networks and the core of information technology. Due to the fact that servers are specifically designed for particular network applications, there are significant differences between servers and microcomputers (ordinary PCs) in processing power, stability, reliability, security, scalability, and manageability. The biggest difference is the reliability in a multi-user and multi-tasking environment. Users who use a PC as a server have experiences with sudden shutdowns, unexpected network interruptions, and frequent data loss. This is because the design and manufacturing processes of a PC do not guarantee the reliability in a multi-user and multi-tasking environment. Once serious failures occur, the economic losses will be unpredictable. However, a server serves the entire network of users and needs to work non-stop 24/7, so it must have extremely high stability. On the other hand, in order to achieve high speed to meet the needs of numerous users, the server is equipped with symmetrical multiprocessing (SMP) and a large amount of high-speed memory. Its motherboard can simultaneously install several or even dozens or hundreds of CPUs (the CPUs used in servers are not ordinary CPUs, they are developed and produced by manufacturers specifically for servers). Of course, the memory in servers is also fundamentally different in terms of capacity, performance, technology, etc. In addition, to ensure sufficient security, the server uses many technologies that ordinary computers do not have, such as redundancy technology, system backup, online diagnosis technology, fault prediction and warning technology, memory error correction technology, hot-swappable technology, and remote diagnosis technology. These technologies allow most failures to be repaired in a timely manner without stopping the server and make it highly manageable.