Hi... I have a wifi connection in my house through a router... 4 of us are using the connection... I just want to ask about how to block some websites so the connection wouldn't be for something else not important... How to block websites so that other wifi users in my house can't access...

Content filtering can be addressed through one of several approaches:

1. The easiest is to use a router that has parental control features. The undesirable sites are configured for wholesale blocking or on a per user or machine basis.
   
2. Alternatively, parental control software could be installed on each individual computer and the undesired sites configured. Some browsers and Internet security suite software support parental control features as well.
   
3. Finally, a separate transparent proxy content filter device or proxy server could be added to the network to intercept Internet bound requests and filter accordingly. This option is the most technical and can be the most expensive although there are several free Linux based solutions (example: DansGuardian) that can be used on older hardware.