If you want to put your video files online using HTML5 then it's recommended to have three different formats for a full browser support. Those formats are mp4, ogv and webm.
There are two levels of Microsoft PowerPoint password protection, one to open the presentation and one to enable making changes to presentation. Let's check both of them.
You can set notifications to find out when your collaborators have modified your spreadsheets, and learn what sheets or cells they've modified. You can also choose how often you'd like to be notified.
