add BigBlueButton to the English translation

content/posts/en/2020-03-15_corona.md

@@ -67,7 +67,35 @@ However, if you do not need video or screen transmission,
 we would request that you use the Mumble tool instead (see below)
 to save resources.
 
-### 2. Moodle
+### 2. BigBlueButton
+
+[BigBlueButton](https://bigbluebutton.org/) provides video conferencing and a lot more, to
+facilitate and improve online teaching.
+This includes an interactive whiteboard
+that the presenter can use alone,
+or all participants can share as a whiteboard,
+or on which anyone can create presentation material.
+
+The solution also offers extensive Moderation and collaboration opportunities,
+so-called "breakout rooms",
+to temporarily split a group into smaller groups,
+and a lot more.
+
+#### Where can I find BigBlueButton?
+
+In addition to the [demo instance](https://demo.bigbluebutton.org/gl/),
+Teckids e.V. provide their own BigBlueButton instance,
+which is specifically provided for Educational use.
+The address for the latter is [bbb.teckids.org](https://bbb.teckids.org).
+
+#### Do I need an account for BigBlueButton?
+
+Yes. To create a room you need an account (see Teckids account below).
+The access to existing rooms depends on the settings for the room.
+This includes the possibility of allowing guest access,
+in which case no account would be required for guest users.
+
+### 3. Moodle
 
 Moodle is a learning platform for managing online courses,
 creating tasks and uploading learning material.
@@ -104,7 +132,7 @@ Courses can also be secured with passwords.
 No, Moodle works entirely in the browser.
 However, there is also a Moodle app for smartphones.
 
-### 3. Nextcloud
+### 4. Nextcloud
 
 Nextcloud is a platform for managing files
 and sharing them either publicly or privately.
@@ -132,7 +160,7 @@ that allow uploads by non-registered participants.
 Nextcloud can be used in the browser, but there is also software for
 Synchronization with a computer or with Android or iOS devices.
 
-### 4. Mumble
+### 5. Mumble
 
 Mumble is software that you can use to hold online voice conferences.
 This can even work reliably with quite poor internet connections