Capture another computer via internet without static IP address

You can capture another computer over internet

for example You are in Ahmedabad and your friend in Mumbai and you want install a software in his computer

just install TEAM VEIWER in your machine after installation teamveiwer you get a id of password the id or password you give your friend and say him to install teamveiwer in his machine and he also get id and password so just his id and password give your machine and your id and password give in his machine and after you can access his machine.