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EB:  In this website, and in informal convsersation, "EB" is short for "eclipsing binary" -- of any kind!  Not to be confused with "EB" in the GCVS or VSX, which means an eclipsing binary with a beta Lyrae light-curve morphology, as opposed eclipsing binaries with EA or EW light curve morphologies.  Both of the general variable star books listed in the bibliography (i.e. Percy, or Hoffmeister et al.), explain the differences between the different types of EBs.

ToM:  The most common observation of eclipsing binaries made by amateur astronomers is the Time of Minimum Light, herein abbreviated as "ToM".  This is the time of the centre of the eclipse as recorded on a light curve.  The intent of the observations and the estimation of the ToM is that it is the time when the eclipsing star is half way through its passage in front of the face of its companion, as viewed from earth.  Erroneous observations, and star spots, can cause the ToM derived from the light curve to differ from the time of the geometric phenomenon.

Next:  General notes on what stars to observe.

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