I found this online:

Code:
'The following source code concatenate two strings.

Dim str1 As String = "ppp"
Dim str2 As String = "ccc"
Dim strRes As String = String.Concat(str1, str2)
Console.WriteLine(strRes)

'The following source code concatenates one string and one object.

Dim obj As Object = 12
strRes = String.Concat(str1, obj)
Console.WriteLine(strRes)

'The Copy method copies contents of a string to another. The Copy method takes a string as input and returns another string with the same contents as the input string. For example, the following code copies str1 to strRes.

strRes = String.Copy(str1)
Console.WriteLine("Copy result :" + strRes)
My question is, what is the advantage of using concatenate and copy over something like this:

Code:
'concatenate
Console.WriteLine(str1 + str2)

'copy
strRes = str1
Console.WriteLine(strRes)
Thanks.