Connecting two or more computers together in such a way that they behave like a single computer. Clustering is used for parallel processing, load balancing and fault tolerance.Clustering is a popular strategy for implementing parallel processing applications because it enables companies to leverage the investment already made in PCs and workstations.

It means connecting them all under one server, am I right with that? Is there a difference between computer cluster and web clustering?

Clustering means the ability of several servers to connect to a single server. It is a group of servers and other resources that act like a single system.

Clustering is a way of using multiple servers to act as one virtual server - letting you keep your machines in various locations, but access their databases as if it was one big database. Much easier for access, and you don't need to buy a huge server and throw away the old one once you've maxed out the drive capacity - just add more machines.

Upon researching in the internet, I found out that Clustering is focus on distributing work loads to each server and managing the transfer of workloads.

A cluster is a group of minimum two computers (nodes) and maximum can be countless. One of the principal concepts of a cluster is to provide unceasing service with high availability (HA). The process of connecting servers and forming cluster is known as clustering.
1 Computer = 1 Node = 1 Server and Group of Node/Server = Cluster.

Clustering, in the context of databases, represents the capability of several web servers or circumstances to get connected to a single data source. An example is the gathering of storage and procedures that communicates with a data source, which is the set of physical data files that actually store data.

Cluster is nothing but the group of multiple server connected to each other to provide high performance. The cluster contains the similar type of server grouped together.

It protects data, keep your application running though one of the server fails.

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A cluster is a collection of commodity components to provide scalability and availability at a low cost. With this in mind, it is possible to create a database cluster for high-end enterprise applications by storing and processing information on commodity nodes

A cluster is a subset of data which are similar. Clustering (also called unsupervised learning) is the process of dividing a dataset into groups such that the members of each group are as similar (close) as possible to one another, and different groups are as dissimilar (far) as possible from one another. Clustering can uncover previously undetected relationships in a dataset. There are many applications for cluster analysis. For example, in business, cluster analysis can be used to discover and characterize customer segments for marketing purposes and in biology,