If we would like to provide right protection for our computer we should be aware that many there are many different treats that may occur during internet surfing. First of all to surf safe we need some knowledge about the water in which we are going to surf. It is the same with internet. Basic knowledge and rules should be in memory of every user. If we know more than that we can drown in deep water we can get to equipment. If we would like to browse the internet (surf waters) we need got equipment (surfing board). This board can’t have a huge hole in it because we will be another submarine on the bottom of the sea. Assuming spam filter is like our board we can’t allow it to let pass any unwanted and possibly dangerous messages. Another example is our surfing suit. If it got holes than more chill air is getting close to our body and we can forget about comfortable surfing. Now lets compare web filter or url filter to our surfing suit. If there are holes in our filters than we can be sure that more and more untrusted and dangerous sites, contents will be getting close enough to deal some damage to our precious data or details. So as you see, the best result can be achieved only thanks to synergy of knowledge and well checked and professional equipment.