Both arrays and vectors can be accessed using a value (such as my_vec[4]). However, if you want to manipulate a section of the array, then you would take a slice from the array. A slice is like a window to a part of the original thing.

To create a slice, use this:

let my_slice = &my_vec[1..5];  

A slice also has no predefined size: it can be 2 bytes, or it can be 202 bytes. Due to this, the size of the slice is not known at compile time. This is important to know, because it prevents certain methods from working.