The reason I have the slashes in front of the double quotes like this is so they are properly escaped within PHP. This is because php uses these double quoted to indicate the start and stop of a string literal. If you want a double quote to be printed from within a string literal you must escape them with the slash or it would just signify the end of the string and whatever comes after the quotes will not be printed. You will also likely get an error message for whatever occurs after that.
Here is a link to the php page on the topic of strings: