Suppose your presentation contains sensitive or confidential data, or you might want only certain people to be able to open and modify a presentation. In that case, you can encrypt the file and protect it with a password. Generally, to ensure that no one can change the presentation, it is better to save the presentation as images or as a PDF file.

The new PowerPoint Designer feature automatically generates design ideas on the new Design Ideas pane. By default, this pane appears on the right side of the slide and can be very useful for creative users:

If you want to stress the cyclic nature in a diagram, schema or chart will be useful to create circling arrows or arrows in a circle and use them for the background picture.
PowerPoint proposes several predefined features for circular diagrams, such as SmartArt, and you can find plenty of them on the Internet. However, it is easy to create your own diagram to give your presentation a professional look.

When you create the process flow chart, process map, business flow diagram, or data flow diagrams and UML activity diagrams, you often need to add some text or labels to the connectors. Unlike many other free and commercial diagram drawing packages, Microsoft Office shapes provide extremely rich text formatting features.

If you create a diagram, graphic, or even flow chart with cyclic procedures, you can use predefined SmartArt graphics, but the Cycle diagrams set is very limited. Moreover, modification of SmartArt graphics is not easy, and sometimes you will spend a lot of time on even trivial changes. So, it is easier to create your own arrows in a circle diagram if you want to add a fresh look to your presentation.

It is polite to reply to every received message, even if you don't have a time to process the message. For example, if you get lots of CVs and cover letters, you can automatically send a reply to every email, and, just when you have time, process them and send an appropriate email with detailed information.

By default, PowerPoint automatically checks the spelling of the entire presentation: all slides, outlines, notes pages, and handout pages. You can disable this feature and skip spell-checking for certain text.

While working in Excel, you may need to find certain types of cells in your worksheets. For example, cells that contain comments, formulas, or only formulas with errors. See how to select all the embedded charts on the worksheet and how to select a large data range in one click in Excel.

Named ranges (also known as defined ranges) are a powerful feature in Excel that allows you to assign a symbolic name to a cell, range of cells, or formula. These defined names are a convenient replacement for the address of a cell, data range, or formula in other formulas, charts, diagrams, shapes, etc.

Excel supports different formats for positive and negative numbers. You can combine text and formatted values to make the display more presentative. Another numeric format is a timestamp, and you can find a difference between two timestamps and display it in days, hours, and minutes. However, Excel does not handle well negative timestamp differences.