Data type - User defined

User defined data type can be any data type using a Type statement which is more related to groups of variables. Declaration must be done at module level above the sub procedure, otherwise compile error: Invalid inside procedure as below.

Syntax : 

Type MyType
    Field1 as Any Data type
    Field2 as Any Data type
    .
    .
End Type

The above syntax must be declare at module level and below statement is inside sub procedure.

Dim MyVar as MyType

From here we can access Field1,Field2,... and etc.

Refer below for example:

VBA Vode:

Option Explicit
Type MyDetails
    Myname As String
    MyAge As Integer
    MyBirthDate As Date
    MyMarried As Boolean
End Type
Sub DataTypeExample_UserDefined()

    Dim MyBio As MyDetails
    
    MyBio.Myname = "Nazri"
    MyBio.MyAge = 50
    MyBio.MyBirthDate = "05/06/1978"
    MyBio.MyMarried = True
    
    MsgBox ("My name is " & MyBio.Myname & " my age is " & _
            MyBio.MyAge & " and married is " & MyBio.MyMarried)
    
End Sub

Note:
This User defined data type is more to static, we can't changed this inside our code only at design stage.

Read more about User defined data type, macro enabled excel, excel macro,
vba coding, vba code at below links.

Microsoft Reference-User-defined-data-type
Other Reference-User-defined-types.htm

Leave your comments if you have any request.
Practice makes perfect.
Thank You.

Data type - Object

Object data type is refer to any objects in excel and store as 32-bit (4-byte) and Set statement must be use after declares otherwise Run-time error '91': Object variable or with block variable not set in syntax.

Syntax : Dim MyVar as Object
               Set MyVar = Object

Object can be any objects assigned to it for example: Workbook, Worksheet, Chart and etc
(Refer below link for Object model).

Below Example is to check whether active sheet is empty or not?

VBA Vode:

Option Explicit
Sub ToCheckActiveSheetEmpty()
    
    Dim MyWS As Worksheet
    Dim MyRng As Range
    Set MyWS = ActiveSheet
    Set MyRng = MyWS.UsedRange
    
    If WorksheetFunction.CountA(MyRng) = 0 And _
    MyWS.Shapes.Count = 0 Then
        MsgBox "Sheet " & """" & MyWS.Name & """" & " is empty", _
        vbInformation, "https://mrvba.blogspot.com"
    Else
        MsgBox "Sheet " & """" & MyWS.Name & """" & "  is not empty", _
        vbInformation, "https://mrvba.blogspot.com"
    End If

End Sub

Note: There are 2 objects inside the example. 1st Worksheet and 2nd is Range.

Read more about Object data type, excel training beginners, coding in vba,
excel training online, visual basic for applications at below links.

Microsoft Reference-Object-data-type
Microsoft Reference-Object-model

Leave your comments if you have any request.
Practice makes perfect.
Thank You.