Implicit Conversion

Is invoked automatically when a value of one data type is assigned to a value of another. Widening casts are often implicit.
An implicit data type conversion is a conversion that happens automatically.
VBA provides implicit conversion for a large number of data types
A string representation of a number will even be implicitly converted to a Long

Dim sNumber As String 
sNumber = "20" 
Dim lNumber As Long 
lNumber = sNumber 

You can assign a string to a numeric variable if the string represents a number
You can also assign a numerical value to a string variable.

Dim lNumber As Long 
Dim sNumber As String 
sNumber = "100" 
lNumber = sNumber 
sNumber = lNumber 
Call MsgBox(sNumber) 

Variant Data Type

When a variable is declared as a Variant data type all the conversions are done implicitly.
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