Final answer:
In the Go programming language, the underscore is used as a placeholder variable in for loop iteration.
Step-by-step explanation:
In the Go programming language, when using a for loop to iterate over elements in an array, slice, map, or what Go calls a 'range', the underscore (_) is used as a placeholder variable in for loop iteration.
It allows you to ignore those values and focus on other parts of the loop.
Here's an example:
for _, value := range someSlice {
fmt.Println(value)
}
In this case, the underscore (_) is used to ignore the loop index and only focus on printing the value.
Additionally, Go was originally built for programs related to networking and infrastructure. It was intended to replace popular high-performance server-side languages like Java and C++.
Today, Go is used for a variety of applications like cloud and server side applications, DevOps, command line tools and much more.