Welcome to the 2008 TASI lectures on the exciting topic of `tools and technicalities' (original title). Technically, LHC physics is really all about perturbative QCD in signals or backgrounds. Whenever we look for interesting signatures at the LHC we get killed by QCD. Therefore, I will focus on QCD issues which arise for example in Higgs searches or exotics searches at the LHC, and ways to tackle them nowadays. In the last section you will find a few phenomenological discussions, for example on missing energy or helicity amplitudes.