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You may look into Wikipedia or short summary for students. Everybody says that there are two instructions for the same thing. But nobody tells why?

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Branches allow for conditions. But allowing for conditions takes up more bits in the instruction. Therefore, a branch's address is only 2^16 bits and only allows you to branch 2^15 - 1 instructions backward or 2^15 instructions forward.

A jump is unconditional and the bits saved by leaving out the condition can be used for the address. A jump allows for a 26 bit address and so can jump much further in the code than a branch. At the expense of not being conditional.


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