readme update

README.md

@@ -29,6 +29,24 @@ Unlike the Chrome devtools location sensor, overriding the locale does not chang
 Data spoofed with Vytal can not be detected. Although other extensions which spoof data can be detected. https://vytal.io allows you to compare and test these various tools. A red x signifies that the scanner has detected tampered data. A green check means that no tampering has
 been detected. Clicking on the table row of the tampered data will bring up a modal box showing the type of detected tampering.
 
+## Data Retrieval Methods
+
+### Top Window
+
+The top window returns the topmost window in the hierarchy of window objects.
+
+### Initial Load
+
+Data spoofing methods can have slight delays between the loading of a webpage and the data being spoofed. Data can be retrieved at the very start of a webpage loading before the data can be spoofed.
+
+### Frame
+
+A frame is a part of a web page which displays content independent of its container, with the ability to load content independently. The HTML or media elements shown in a frame may come from a different web site as the other elements of content on display.
+
+### Web worker
+
+Web Workers are a simple means for web content to run scripts in background threads. The worker thread can perform tasks without interfering with the user interface. Once created, a worker can send messages to the JavaScript code that created it by posting messages to an event handler specified by that code (and vice versa). Extension content scripts cannot be injected into workers
+
 ## Types of Tampering
 
 ### Failed Date.prototype.setDate.toString()