[Go] GOPATH

export GOROOT=$HOME/go
export GOPATH=$HOME/gopath
export PATH=$PATH:$GOROOT/bin

Reference: https://golang.org/doc/install

It is better to install go by downloading binary file.
If you use apt-get to install go, do not set "export GOROOT=$HOME/go"
To unset that, type "unset GOROOT"