Remember, Microspeak is not merely for jargon exclusive to Microsoft, but it's jargon that you need to know.

The term brownbag (always one word, accent on the first syllable) refers to a presentation given during lunch. The attendees are expected to bring their lunch to the meeting room and eat while they listen to the presentation.

A brownbag could be a one-off presentation, or it could be a regular event. The speaker could be an invited guest, or the presenters may come from within the team. In general, the purpose of a brownbag is to familiarize the audience with a new concept or to share information with the rest of the team. Sometimes attendance is optional, sometimes attendance is mandatory, and sometimes attendance is optional but strongly recommended, which puts it in the murky category of mandatory optional.

You can learn more about each team's plans in brownbags that we will kick off the week of 2/17 and continue regularly through the month.
Are you going to the brownbag? I'm heading to the cafeteria, want to come along?

It is common for the slides accompanying a brownbag to be placed on a Web site for future reference. Sometimes the presentation is recorded as well.

The term brownbag is sometimes extended to mean any presentation which introduces a group of people to a new concept, whether it occurs at lunch or not.

Virtual brownbag on widget coloring.

That's the (redacted) subject of a message I sent out to our team. The message described the process you have to go through in order to get a widget coloring certificate. It could have been a brownbag but I was too lazy to book a room for it, so I created a virtual brownbag.

Due to scheduling conflicts, we will have to move the presentation to Friday at noon. We apologize for the last-minute change. This is now really a brownbag, so grab your lunch in the cafeteria and join us for a great talk and discussion!

The above is another example of how the term brownbag was applied to something that, at least originally, was not a lunch meeting.