MSXML2.XmlHttp

This is on its way out
Reference - Microsoft XML v6.0
Adding this reference allows you to use the MSXML application programming interfaces from within VBA.
This is an XML parser which supports DOM that can be used in VBA to access and manipulate XML data.
It is possible to treat an XML file as a text file and parse it using traditional methods but is not very efficient.
However because the XML data is structured it is far easier to use an XML parser instead.
There are lots of different type of XML parsers but for the purposes of VBA you will want to use a parser that supports XML Document Object Model (DOM).
An XML parser that supports DOM will take the XML data and expose it via a set of objects that we can program against.

Dim xmlhttp As New MSXML2.XMLHTTP        'whatever version is installed, could be 5.0 or 4.0  
Dim xmlhttp As New MSXML2.XMLHTTP60      'for Microsoft XML, v 6.0  
Dim xmlhttp As New MSXML2.XMLHTTP.6.0    'for Microsoft XML, v 6.0  

CreatObject("MSXML2.XMLHTTP") 
CreatObject("MSXML2.XMLHTTP60") 
CreatObject("MSXML2.XMLHTTP.6.0") 
CreatObject("MSXML2.XMLHTTPRequest60")   'not recommended  

Uses the browser HTTP stack (WinInet), which introduces quirks that can break JSON API calls.
You want the simplest possible GET request
You don't need advanced headers or authentication
Supports proxy and server credentials

Sub Request() 
Dim xmlhttp As MSXML2.XMLHTTP 
Dim sDownloadDate As String 
Dim sResponse As String 

   Set xmlhttp = CreateObject("MSXML2.XMLHTTP") 
   sDownloadDate = VBA.Format(VBA.Now, "yyyy-mm-dd") 
   
   Call xmlhttp.Open("GET", modConstants.g_sURL_PREFIX & modConstants.g_sURL_SUFFIX_COMBINEDINFO & sDownloadDate, False) 

   xmlhttp.send 
   sResponse = xmlhttp.responseText 
End Sub 

GET

This enables you to download an internet file using the Microsoft XML object and is an alternative to using the URLDownloadToFile API.
Requires a reference to the Microsoft XML library
The responseBody method of the XMLHHTP object returns a byte array

Public Function SaveWebFile(ByVal vWebFile As String, ByVal vLocalFile As String) As Boolean 
Dim oXMLHTTP As MSXML2.XMLHTTP 
Dim i As Long, 
Dim vFF As Long 
Dim oResp() As Byte 

    Set oXMLHTTP = CreateObject("MSXML2.XMLHTTP") 
    oXMLHTTP.Open "GET", vWebFile, False 
    oXMLHTTP.Send 
     
    Do While (oXMLHTTP.readyState <> 4 ) 
        DoEvents 
    Loop 
     
    oResp = oXMLHTTP.responseBody 
     
    vFF = FreeFile 
    If Dir(vLocalFile) <> "" Then 
        Kill vLocalFile 
    End If 
    Open vLocalFile For Binary As #vFF 
    Put #vFF, , oResp 
    Close #vFF 
     
    Set oXMLHTTP = Nothing 
End Function 
 
Public Sub Testing() 
    Call SaveWebFile ("http://www.bettersolutions.com/websitelogo.png", "C:\websitelogo.png" ) 
    ActiveSheet.Pictures.Insert "C:\websitelogo.png" 
    Kill "C:\C:\websitelogo.png" 
End Sub 

POST

Dim xmlhttp As MSXML2.XMLHTTP 
Dim myurl As String 

Set xmlhttp = CreateObject("MSXML2.XMLHTTP) 
myurl = "http://requestb.in/15oxrjh1" 
xmlhttp.Open "POST", myurl, False 
xmlhttp.setRequestHeader "Content-Type", "application/x-www-form-urlencoded" 

xmlhttp.Send "name=codingislove&email=admin@codingislove.com" 
MsgBox (xmlhttp.responseText) 

xmlhttp.setRequestHeader "Content-Type", "application/json" 
'assumes the data returned is in a very basic key-value pair json format
'{"id":1,"title":"hello"}

POST

Dim SoapRequest As String 
Dim Server As String 
Dim Request As New MSXML2.XMLHTTP 
Dim Response As String 

Server = "http:///service/vestaService/" 
SoapRequest = [A2].Value 
    With Request 
        .Open "POST", Server, False 
        .send SoapRequest 
        Response = .responseText 

    End With 
Debug.Print Response 
MsgBox Response