What type of scaling is best for increasing a server's capabilities?

Vertical scaling, also known as "scaling up," involves adding more resources to an existing server, such as increasing the CPU, RAM, or storage capacity. This approach is effective for enhancing a server's capabilities because it directly enhances the performance and capacity of that single instance. It is often easier to implement than other scaling methods, as it typically does not require significant changes to the application architecture.

In vertical scaling, the system becomes more powerful as resources are added, allowing it to handle increased workloads without needing to modify the overall architecture or the way that applications are deployed. This is particularly beneficial for applications that are not designed to run in distributed environments.

In contrast, horizontal scaling involves adding more servers to distribute load and can complicate architecture by requiring additional coordination and synchronization. Cloud scaling is a broader concept that can include both vertical and horizontal scaling methods, while distributed scaling focuses on spreading the load across multiple servers that work together.