Over the last 30 years man-made CFCs have been the main cause of stratospheric ozone depletion. CFCs however, are not the only ozone-depleting chemicals. Other ODCs include the methylhalides, carbon tetrachloride (CCl4), carbon tetrafluoride (CF4), and the halons which contain bromine instead of chlorine.
Part of the Internet applications glossary: Yahoo! is an Internet portal that incorporates a search engine and a directory of World Wide Web sites organized in a hierarchy of topic categories.
To get rid of Yahoo search, open Firefox's Preferences and click on the Search tab. (You can also head directly to the search tab in Preferences by typing a letter in Firefox's search bar to call up the search window before clicking Change Search Settings at the bottom of said window.). Screenshot by Matt Elliott/CNET.From the search tab in Preferences, you'll see Yahoo is selected in the Default Search Engine area. Use the pulldown menu to return it to Google or select one of the other search providers. Just below, there's also a checkbox for Provide search suggestions.rom the search tab in Preferences, you'll see Yahoo is selected in the Default Search Engine area. Use the pulldown menu to return it to Google or select one of the other search providers.