I'm sorry if my question is too simple, but I am self-studying FIR because we have to report it in our class. I am using the book of Proakis and Manolakis as reference.
Under 7.2 Structures for FIR systems:
In general, an FIR system is described by the difference equation (7.2.1)
or evidently, by the system function
Under 7.2.1 Direct-Form Structure:
The direct-form realization follows immediately from the nonrecursive difference equation given by (7.2.1) or, equivalently, by the convolution summation
I can see that they almost look the same apart from the bk in 7.2.1 and h(k) in 7.2.4. Question is, how are they different or related to each other? Sorry if you find my question too basic. Thank you in advance for the help!