Question: wget how to use proxy?
Answer: Add below line(s) in file ~/.wgetrc or /etc/wgetrc: http_proxy = http://[Proxy_Server]:[port] https_proxy = http://[Proxy_Server]:[port] ftp_proxy = http://[Proxy_Server]:[port]
Set proxy variable(s) in a shell manually: ... 
Add below line(s) in file ~/.bash_profile or /etc/profile: