Organisational structures?

[Mongaa]

Hey does someone mind berifly explaining structures to me?  I'm really confused in terms of which structures are centralised and which are decentralised.  I don't understand the difference between hierarchical and bureaucratic structures either.  Someone help me -.-.

[Michelle94]

bureaucratic structure is centralised

all other structures
functional, divisional, matrix are decentralised

there is no difference between hierarchical and bureaucratic structure either
a hieracrchiacal structure is beuraucratic, as you have to "climb the ladder" to reach a decision making power position.
wheras all other structures you do not need to "climb the ladder"