an anonymizer is a proxy. what that means is it makes requests on your behalf. when you use a proxy, your browser/ftp client/telnet client etc. sends a request, including the ip/url address where you want stuff from, to the proxy server. the proxy server fowards that requst to that server. the server that has the stuff you want logs the requst as coming from the proxy's ip address and not yours, because you didn't actually contact it.
for more information on the subject do a search for proxy servers
Bukhari:V3B48N826 “The Prophet said, ‘Isn’t the witness of a woman equal to half of that of a man?’ The women said, ‘Yes.’ He said, ‘This is because of the deficiency of a woman’s mind.’”