Among the web hosting terms you might come across and say to yourself, “Huh?” is the term load balancing. Simply put, load balancing is a method of balancing a server load, just as the name implies. If a web hosting company has some large clients on a few servers, they can distribute the load over many servers, sharing the “weight” so that those few servers are not bogged down.
“High availability can be defined as redundancy. If one server cannot handle a request, can other servers in the cluster handle it? In a highly available system, if a single Web server fails, then another server takes over, as transparently as possible, to process the request.”
If you are running a high-traffic website or other type of Internet service, such as IRC, a gaming server, etc., finding a web host that uses load balancing may be important to you. If you are running a small business site and use your site more as an online business card, load balancing may just be a term that is nice to know, but not necessarily relevant.