./configure make make install for Unix/Linux users T-Shirt

Traditionally software packages on Unix/Linux systems had to be installed by downloading the source code, compiling and installing it using the well-known command sequence: ./configure make make install Nowadays, sysadmins and Unix/Linux users can use package managers to install software with the added benefit that these managers also take the pain out of dependency management. Still installing from source is sometimes necessary and I've heard of hardcore sysadmins who actually prefer it. If you are one of those or just nostalgic you may enjoy a shirt or another product with these commands printed in a black monospace font on it.