How to connect siemens plcs with pc?

You shall need:

(1) A Communication Card / Dongle

&

(2) Software based upon PLC you want to connect Like Step5 or Step7

for connecting PLC With PC you need

a programming software viz SIMATIC MANAGER ,S7-200 MICROWIN depend upon which PLC you are using 

and a communication cable like PPI, MPI, MODBUS 

you should have cable connection from PC tp PLC as (ppi,or MPI,and profibus or another) it is hardware connection

and have PLC programing on your PC as software connection

step7300 plc i want to connect, which software needed for connecting