7.1 Introduction7.2 Measurement Method and Data7.3 Representation of Physical Phenomena7.4 Forward Problem and Model7.5 Uniqueness Theory and Direct Reconstruction Method7.6 Back-Projection Algorithm7.7 Sensitivity and Sensitivity Matrix7.8 Inverse Problem of EIT7.9 Static Imaging7.10 Time-Difference Imaging7.11 Frequency-Difference ImagingReferences