git ignore and guid tag formalize

.gitignore

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+/.vs/

docs/1.0.md

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     <podcast:integrity type="sri" value="sha384-ExVqijgYHm15PqQqdXfW95x+Rs6C+d6E/ICxyQOeFevnxNLR/wtJNrNYTjIysUBo" />
 </podcast:alternateEnclosure>
 ```
+
+<br><br>
+
+
+## Guid
+`<podcast:guid>`
+This element is used to declare a unique, global identifier for a podcast. The value is a UUIDv5, and is easily generated from the RSS feed url, with the **protocol scheme and trailing slashes stripped off**, combined with a unique "podcast" namespace
+which has a UUID of `ead4c236-bf58-58c6-a2c6-a6b28d128cb6`. Tools like [this one](https://www.uuidtools.com/v5) can help generate these values by hand. Or, language libraries like [this one](https://github.com/sporkmonger/uuidtools) in Ruby are widely
+available.
+
+A podcast gets assigned a podcast:guid once in it's lifetime using it's current feed url (at the time of assignment) as the seed value. That GUID is then meant to follow the podcast from then on, for the duration of it's life, even if the feed url
+changes. This means that when a podcast moves from one hosting platform to another, it's podcast:guid should be discovered by the new host and imported into the new platform for inclusion into the feed.
+
+Using this pattern, podcasts can maintain a consistent identity across the open RSS ecosystem without a central authority.
+
+#### Parent
+`<channel>`
+
+#### Count
+Single
+
+#### Node Value
+The node value is a UUIDv5 string.
+
+#### Attributes
+There are no attributes for this tag.
+
+#### Examples
+Example GUID for feed url `mp3s.nashownotes.com/pc20rss.xml`:
+
+```xml
+<podcast:guid>917393e3-1b1e-5cef-ace4-edaa54e1f810</podcast:guid>
+```
+
+Example GUID for feed url `podnews.net/rss`:
+
+```xml
+<podcast:guid>9b024349-ccf0-5f69-a609-6b82873eab3c</podcast:guid>
+```