Can you explain what is meant by the term system scalability?

System scalability is the ability of a system to operate efficiently as the load or data volume increases. It indicates how easily the system can be expanded to handle more users, requests, or data.

There are two main types of scalability:

• Vertical scalability (scale-up) — increasing resources of a single server (e.g., adding RAM or processors).
• Horizontal scalability (scale-out) — adding new servers or nodes to the system.

In the context of Golang, scalability is often achieved through effective use of goroutines, channels, and distributed systems.

An example of a simple HTTP server that can handle many requests in parallel thanks to goroutines:

package main

import (
    "fmt"
    "net/http"
)

func handler(w http.ResponseWriter, r *http.Request) {
    fmt.Fprintf(w, "Hello, World!")
}

func main() {
    http.HandleFunc("/", handler)
    http.ListenAndServe(":8080", nil)
}

Such a server can process many requests simultaneously, which is part of scalability.