Google Alerts currently offers 6 variations of alerts - 'News', 'Web', 'Blogs', 'Comprehensive', 'Video' and 'Groups'.
- A 'News' alert is an email aggregate of the latest news articles that contain the search terms of your choice and appear in the top ten results of your Google News search.
- A 'Web' alert is an email aggregate of the latest web pages that contain the search terms of your choice and appear in the top twenty results of your Google Web search.
- A 'Blogs' alert is an email aggregate of the latest blog posts that contain the search terms of your choice and appear in the top ten results of your Google Blog search.
- A 'Comprehensive' alert is an aggregate of the latest results from multiple sources (News, Web and Blogs) into a single email to provide maximum coverage on the topic of your choice.
- A 'Video' alert is an email aggregate of the latest videos that contain the search terms of your choice and appear in the top ten results of your Google Video search.
- A 'Groups' alert is an email aggregate of new posts that contain the search terms of your choice and appear in the top fifty results of your Google Groups search.
Google sends the email in three types there are - 'Once a week', 'once a day' and ' as it happens'
- A 'once a week' (recommended) option can send emails automatically once a week for your search terms.
- A 'once a day' (it can sends mail frequently mails of maximum results like bulk) option can send emails automatically once a day for your search terms.
- A 'as it happens' option can sends the mails when it happens.It can sends more mail frequently mails of maximum results like bulk when compare with 'once a day'.