Yahoo! places tracking cookies from all their sites. even if you are useing their hosting package, they still use cookies, and it is part of what you have to agree to when using their services. geocities is their free hosting.
a phishing site is a fake site that tries to get you to enter your personal information for ID theft, financial theft. biggest fake sites are for banks, paypal, and ebay. generally sent in an email. if you right click on a link, and choose properties, it will show you the destination of the link.
If you are not sure, do not click on the link, type the address you normally use in your browser and login in.
any site that asks for more than your first name and email address (for a newsletter) is probably a phishing site. never enter personal information on a site that does not have https:// in the address. https means the site is secure. Most phishing sites do not bother with this.