1 collider experiments (the onion structure) - 2 requirements of the LHC - 3 the four LHC experiments - 4 why four, the differences - 5 online selection and computing needs - 6 flow of data analysis, data formats - 7 the analysis process - 8 unpredictability, iterations - 9 an example of detector understanding in early LHC data - 10 some early results