Assuming `name` is a variable of type `String` that has been assigned a value, write an expression to obtain the string containing the second character of `name`. For instance, if `name` is "Smith", the expression should yield "m".

To obtain the second character of a `String` in most programming languages like Java or Python, you can use indexing. Since indexing is zero-based in these languages, the second character is at index 1 (the first character is at index 0). Here's how you would write the expression in Java or Python:

In Java: ```java char secondCharacter = name.charAt(1); ```

In Python: ```python secondCharacter = name[1] ```

The variable `secondCharacter` will contain the value `'m'` if `name` is `"Smith"`.

Extra: When dealing with strings in programming, it's important to understand the concept of indexing and how strings are treated as a sequence of characters. Each character in the string has an associated index, which starts at 0 for the first character, goes to 1 for the second character, and so on until the end of the string.

For example, consider the string `"Hello"`. The character `'H'` is at index 0, `'e'` is at index 1, `'l'` is at index 2, and so forth. To retrieve a particular character, you can use the index inside brackets (in Python) or by calling a method like `charAt()` (in Java).

Knowing how to work with strings and their indices is fundamental in many programming tasks, such as substring extraction, string manipulation, searching, and sorting. It's also important to remember that trying to access an index that is out of the string's bounds (for instance, an index greater than or equal to the length of the string) will result in an error, often referred to as an IndexOutOfBoundsException in Java or an IndexError in Python.