Hi, I had some questions regarding my recent usage of the term “RTL”. By this I mean “right to left”, a characteristic of Arabic and Hebrew. At Microsoft we also call this “bidi” (bidirectional). Here’s a discussion regarding RTL. (I’ve also attached a much more detailed explanation, which includes Microsoft’s recommendations, but it’s in PowerPoint. Hopefully you already use a compatible viewer.) Bidi display of IRIs (URLs/URIs) Bidirectional display of IRIs (an IRI with some Right-To-Left characters, eg: Arabic) has some odd quirks. There’s an IETF WG working on creating an IRI RFC. It’d be nice if we could help ensure that there were reasonable standards for the display of bidi IRIs. The existing IRI drafts suggest using the Unicode Bidi Algorithm to display IRIs, but that has some problems. User and government feedback indicates that our current behavior is a bit unexpected. Currently we have some odd quirks about the display of Bidi IRIs in Microsoft. This is just an example, other places may have different odd quirks. Logical Order IE with LTR context IE with RTL context http://www.microsoft.com http://www.microsoft.com http://www.microsoft.com http://اا1اا.بب2بب.ةة3ةة http://اا1اا.بب2بب.ةة3ةة http://اا1اا.بب2بب.ةة3ةة http://a1a.اا2اا.بب3بب.d4d http://a1a.اا2اا.بب3بب.d4d http://a1a.اا2اا.بب3بب.d4d http://اا1اا.b2b.c3c.بب4بب http://اا1اا.b2b.c3c.بب4بب http://اا1اا.b2b.c3c.بب4بب As we can see, the order of some of the elements may seem counter-intuitive. The highlighted sections start in one direction, but then jump or rearrange direction so that the elements don’t follow the same order. The Unicode Bidi algorithm has the idea that some characters aren’t inherently RTL or LTR. Instead they take on the properties of the characters surrounding them. This is why some pairs get “flipped” in the rendered order. User Expectations Limited usability investigations have demonstrated that users expect IRIs and other paths to be in the form of an ordered list. The “separators” of the various fields vary, but the entire unit is treated as a list. E.g.: http://www.microsoft.com is a list { “http”, “www”, “microsoft”, “com” }. Users expect it to be rendered “in order” with the first element, then second, etc. What is a bit unclear is exactly which direction the users expect the lists to be rendered in. There seem to be 2 main options for what users expect: · Always render the path elements from Left to Right (e.g. “www.microsoft.com<http://www.microsoft.com>”) regardless of the script. · Always render the path elements from Right to Left in a Bidi context (application), e.g.: “com.microsoft.www//:http”, EVEN FOR ASCII IRIs. We need to confirm what the user expectations are for Bidi Display, and ensure that any edits to IETF IRI standards match those expectations.