problem with my template

[eluser]raffie77[/eluser]
[quote author="CroNiX" date="1382468142"]Because you are echoing straight from a controller or model instead of using the output class or view, so that gets output immediately followed by the headers and CI's output, which causes the error because you output something before headers were sent, and then you sent more headers.[/quote]

Ok so do I understand it correctly dat you don't use echo or print(f) in a contorler or model?
instead of that I use return, all the echo's are placed in the view?