Well if your PC or laptop has HDMI output (some have) then you can plug a HDMI cable into the laptop and the other end in the TV.
All laptop will have a graphics out socket (for plugging in an external monitor) so yo ucan use that to conect it to your TV.
To be honest if you search for "connect laptop to TV" you will find loads of web sites giving help, like this one (there are loads of others)
http://www.techradar....ptop-to-my-tv--902693