Why does the column name "source" get rendered in grey in SSMS & VS T-SQL editor?

I have the following simple tSQL to create a table

CREATE TABLE NewsArticles
(id INT NOT NULL IDENTITY(1, 1) PRIMARY KEY,
lastCrawl DATETIME NULL,
snippet NVARCHAR(2083) NULL,
source NVARCHAR(2083) NULL,
title NVARCHAR(2083) NULL,
url NVARCHAR(2083) NULL)

In both Visual Studio 2012 and SQL Server 2012 Management Studio "source" is rendered in grey while the other column names are rendered green in SSMS or black in VS. Why? The word "source" does not appear to be a reserved word in the list of SQL reserved keywords

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Why does the column name "source" get rendered in grey in SSMS & VS T-SQL editor?

1 Answers