Understanding the syntax in =HYPERLINK() in Excel

Hello,

I am struggling with the syntax for using the function:  =HYPERLINK() in Excel (2007). In the help file, it shows the syntax for this function as:

    =HYPERLINK(link_location,friendly_name)

However, I have a hunch that my struggles have more to do with designating Excel folders, workbooks (files), worksheets (tabs), and cell references than it does with the actual syntax.  The following template has been useful in several links I have created in the past:

    =HYPERLINK("[C:\Users\UserName\Documents\UserFolder\UserFileName.xlsx]'SheetTab'!A1","CellDisplayText")

However, at other times I have not been able to get it to work. One thing that would help me immensely is if someone could explain a few of the components in this template if it is dissected.  For example, the beginning and end:

    =HYPERLINK(
and
    ,"CellDisplayText")

are straightforward and if eliminated from the help file example above, leave only the "...link_location...," in this case, represented by:

    "[C:\Users\UserName\Documents\UserFolder\UserFileName.xlsx]'SheetTab'!A1"

which can be abbreviated as:

    "[C:\...\File.xlsx]'SheetTab'!A1"
or
    "[Pathway]'SheetTab'!A1"

Now, my first question is:  What is the purpose of the quotation marks and brackets:

    "[...............]........................"

and why are they adjacent to each other in the beginning but separated (by the sheet tab and cell reference) at the end?

The next question is:  What is the purpose of the apostrophes:

    '..........'

on either side of the SheetTab?

Finally, what is the role of the exclamation mark:

    ......!......

between the sheet tab and the cell reference?  Is it a modifier for the preceding SheetTab or for the cell reference which follows?

Thanks

PS I have a more specific follow-up question but I will ask that in another thread.