Do Google and Yahoo both use meta tag: http-equiv="description" or name="description" for search results?

My objective is to have the descriptive sentence of my choosing listed on the both Google and Yahoo. I was told that Google uses %26lt;meta name="description" content="...." /%26gt; and Yahoo uses %26lt;meta http-equiv="description" content="..." /%26gt;. I used both within the header of my website. The search results in Google reflect the descriptive sentence I inserted in the tag %26lt;meta name="description" content="...." /%26gt;. In the Yahoo search results, the descriptive sentence is the first sentence of the beginning paragraph of my index page, instead of the sentence I inserted in my meta tag. I need to know which meta tag to use to accomplish my desired results, or if they both use the same tag. Thank you, in advance for your help.

Do Google and Yahoo both use meta tag: http-equiv="description" or name="description" for search results?
Generally these tags are displayed if the search is on the domain name but often the actual search term is used to decide what the SE will display. If you use your common search terms in the description tag it will help.