Text expansion, also known as text replacement, is the process of typing a short abbreviation — a snippet or shortcut — that is automatically converted into a longer string of text. It is commonly used for names with challenging spellings, frequently used phrases, canned emails, addresses, and regularly shared links.

Typing the shortcut triggers insertion of the corresponding phrase anywhere text can be entered on the device — chats, emails, forms, documents. Most operating systems ship a basic version (macOS and iOS call it Text Replacement), while dedicated tools extend the pattern with synced snippet libraries, fill-in fields, and team sharing.

The practical constraint is not the software but the habit. Identifying opportunities, creating expansions, and training yourself to use them takes time; a library grown slowly outperforms a large batch created at once, because shortcuts added faster than they can be engrained are forgotten and left unused.