Share and collaborate on Office files with Teams
Teams makes it simple to share files and collaborate. If you are working with Word, Excel, PowerPoint, or Visio files, your coworkers may read, edit, and collaborate on them directly from Teams.
Co-edit files
Each team member has access to files that have been uploaded and shared on Teams. You and your team members can co-edit Word, PowerPoint or Excel documents, using Office for the web, Office for Android or iOS, or the latest Microsoft 365 apps.
With this feature, you will not have to fret over other colleagues working on the same document or check files out. Simply open the file you require to edit, and any changes that are made by other colleagues will merge while you work effortlessly.
Just click on the file’s More Options (…) and choose where you would like to edit the file.
Need to talk to other team members whilst working on the file in Teams? Select the Conversation box 
This will allow you to chat to others and @ other colleagues.
You can also add comments to specific sections of the document using the speech bubble button 
Share Files Outside of your Team
Word, Excel, Visio or PowerPoint files can easily be shared outside of your team using the Desktop or Web app. Click on the share button 
Once you have updated the Link Settings, you can then choose the name, group or email of people you wish to send the link to. Click on the pencil icon to select if they can edit the document or view only, type the message and then click send.
Alternatively, you can also copy the link using the Copy link button 
Check out a document
You can stop collaboration on a document, perhaps while you make major revisions.
Right-click on the document and choose ‘Check out’.
A checked-out document gets a little arrow marker next to the name.
Hover the mouse over the icon to see who checked out the file.
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