You should KNOW 

1. The properties of logarithms as given e.g. in JIT p. 163.
These must be understood and memorized.  All except the change of base formula can be easily understood in terms of the definition
of a^(nm) as "the number to which you raise a to get x" and 
familiar facts about powers.  For example  
log_a(xy) =log_a x+log_a y because  a^(n+m)  = a^n a^m (Think about it.)

2. How to use the change of basis formula and your calculator
to find  log_a x in terms of either natural or common logs.

You should be ABLE TO

1. Use properties of logarithms to simplify and/or combine 
log and exponential expressions, and solve equations of 
various kinds involving logarithmic and exponential functions.

2. Solve a variety of problems about exponential
growth and decay, including compound interest, 
population growth, radioactive decay. (This 
will be a continuing thread.)