The short summary under your page's title in Google results, written to get people to click.
Like the blurb on the back of a book: it doesn't change the story, but it decides who picks it up.
Every page on a law firm's site shared the description "Welcome to our website." Searchers could not tell the family law page from the real estate page, and clicked a competitor instead.
Managed Search writes and updates meta descriptions as part of monthly site optimisation.
Why does Google show different text than mine?
Google picks the text it thinks best matches the search. A clear, specific description gets used more often.

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