Word, Excel & PowerPoint explained
A plain-English guide to the three core Microsoft Office apps — what each one does, when to use it, and how to get started.
Word, Excel, and PowerPoint are three of the most widely used business apps in the world. They come with most Microsoft 365 plans — either as web apps (in your browser) or as full desktop apps installed on your computer.
Quick summary
Word is for documents — letters, reports, proposals. Excel is for numbers and data — budgets, lists, calculations. PowerPoint is for presentations — slides with text, images, and charts. All three work in your browser without any installation, and files are saved to OneDrive so they're always backed up.
Microsoft Word
Word is a word processor — it's designed for creating and editing text-based documents.
Common uses:
- Business letters and proposals
- Reports and whitepapers
- Contracts and agreements
- Meeting agendas and minutes
- Any long-form written document
How to open it: Go to microsoft365.com and click Word in the app launcher. Or, on your computer, open the Word desktop application.
Saving your work: Word documents are saved as .docx files. If you use Word on the web, your file is saved automatically to OneDrive. In the desktop app, you'll be asked where to save the file.
Microsoft Excel
Excel is a spreadsheet application — it organizes data into rows and columns, and can calculate, analyze, and visualize that data.
Common uses:
- Budgets and financial forecasts
- Invoices and expense tracking
- Inventory lists
- Project timelines and task lists
- Simple databases (contacts, products, etc.)
Key concept — formulas: Excel can perform calculations automatically. For example, if you type numbers in a column, you can add a formula at the bottom that sums them all. Excel has hundreds of built-in formulas for everything from simple addition to complex statistical analysis.
How to open it: Go to microsoft365.com and click Excel, or open the desktop application.
Excel files are called workbooks
An Excel file is called a workbook. A workbook can contain multiple sheets (tabs at the bottom). Each sheet is a grid of rows and columns — the individual boxes are called cells.
Microsoft PowerPoint
PowerPoint is a presentation tool — it creates slideshows for meetings, pitches, training, and more.
Common uses:
- Client presentations and pitches
- Team meetings and all-hands briefings
- Training materials
- Marketing decks
Key concepts:
- A file is called a presentation
- Each screen is a slide
- You present slides in order (press F5 or click the presentation icon to start)
- Slides can contain text, images, charts, videos, and shapes
How to open it: Go to microsoft365.com and click PowerPoint, or open the desktop application.
Web vs desktop apps
Web apps (free with any Microsoft 365 plan)
- Work in any browser
- No installation needed
- Auto-save to OneDrive
- Slightly simpler features
- Great for most everyday tasks
Desktop apps (Business Standard and above)
- Installed on your computer
- Full feature set
- Works offline
- Better for complex documents and spreadsheets
- Required for some advanced formatting
For most writing, budgeting, and basic presentations, the web apps are perfectly capable.
Common questions
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