keywords are an essential part of finding a website using a search engine, websites that have got usefull and well thought out key words and phrases will be much easier to find on the internet than those that don’t. If i site has a poor selection of keywords it will not be found very often if at all on the internet, which then means that there is not much traffic to the site but it also will not make its way up the search results in something like google, which will then make it fall further.
Here is a list of keywords or phrases that are best suited to finding FaceBook.
“Find a friend”

This search term seemed to be highly related with facebook, showing a significant number of related results as shown in the screenshot below, so I belive this is an effecive way to find the website.
“Online Photo”

This term is used greatly to find facebook, as it allows users to upload photos online and all of the friends they have added on the site are able to view and comment on them.
“Social Network”

This term is used the most to find facebook, as it is a very general term that is used to find a vast amount of social network
“Application”
This keyword is used quite frequently as Facebook has got many different games and applications available to its users, some of which are very popular online
“Social Media”
This is a term used for all the social networking sites that allow users to upload and view things like videos, statements, photographs, and would be a very effective keyword for Facebook to use.
“Status Update”
A term used a lot in the social networking industry and is normally the main point to websites such as this so it is a very useful keyword.
“Farmville”
One of the most popular online games at the minute and is only available on Facebook, so using this as a keyword will link to the Facebook Site
“Fan Pages”
Each band or actor has normally got a fan page on Facebook, so this phrase is essential in a search engine
“Facebook Search”
Essential keyword as it allows people to instantly search for users or fan pages etc, directly from the search engine, making finding people much faster and easier.
“Connect with family”
This is a common phrase used, possibly by relatives that have moved to a different country etc, to communicate with ones back home
These keywords I believe sum up most of the workings of Facebook and all of the likely things a user is likely to search for trying to find the Facebook website.