Word switches the mode on from the Review tab or with Ctrl+Shift+E. From then on, added text is underlined, removed text is struck through, and each reviewer's edits take their own colour, so a document passed round a team shows who wanted what. The owner then walks through the proposals in order and accepts or rejects each, and Word moves to the next. Word for the web offers a narrower set of these tools than the desktop application, though Microsoft says most reviewing can be done there.
Suggesting mode in Google Docs
Google Docs names the same idea suggesting mode. Anyone with comment or edit rights can switch from Editing to Suggesting, and their typing turns into suggestions that the owner reviews, one by one or all at once. The practical difference is where the document lives: a Docs file is always shared and live, while a Word file is often emailed, which is how tracked changes end up travelling with it.
Before the file leaves the building
Microsoft is explicit that the No Markup view hides changes only for the moment and that they reappear when the file is next opened; the only way to remove them is to accept or reject them. Its recommended final check is the Document Inspector under File, Info, Check for Issues, which reports leftover revisions, comments, hidden text and personal details stored in the file properties.
Tracking is also different from version history: history records every saved state automatically, whereas tracking records proposals someone has to decide on. In live co-authoring the two often run together. Where the content itself is confidential, a sensitivity label protects the file; tracking does nothing of the kind. The documents and word processing and collaboration and meetings topics both lean on this review cycle.