What data is stored in a pointer inside a slice structure?

A slice structure in Go contains three main fields:

1. Pointer — the address of the first element of the array that the slice references. This is not necessarily the start of the entire array, but the start of the slice within the array.

2. Length — the number of elements accessible through the slice.

3. Capacity — the maximum number of elements that can be held, starting from the pointer, without allocating new memory.

An example of a slice structure (simplified):

type SliceHeader struct {
    Data uintptr // pointer to the first element
    Len  int     // length of the slice
    Cap  int     // capacity of the slice
}

Thus, the pointer inside the slice points to the first element of the slice in the underlying array, allowing efficient work with subarrays without copying data.