In my opinion: Merge - you take one or more things and mix them together resulting in one cohesive thing. Merging lanes on a highway, 2 or more lanes become 1 and from then on you never knew the one lane came from many. Integrate - you take one thing and make it fit into another. Integrating immigrants into a culture would mean you teach immigrants how to conduct themselves within another culture. Incorporate - you take one thing or parts of one thing and blend it in with another. You have two plans to build a house. The first plan has a pool and shed while the 2nd plan does not. I take the plans for the pool and shed and add them, incorporate them, into the 2nd plan to build the house.

In addition to Jane's excellent answer. From a Business Perspective the words can literally mean: "merge" = Join together. Practically this may mean that they become one legal entity but whether they combine their actions in reality will depend upon the nature of the merger. Some mergers result in complete integration and some in complete autonomy. "incorporate" can have the additional meaning that a company has limited liability from then onwards, a Limited Company. "integrate" indicates that there is closer cooperation than "merge", they become part of each other to all intents and purposes.

Not a lot to be honest. They are synonyms We can merge two companies together - integrate two companies together and incorporate two companies together. The legalities of incorporate may be different than the legalities for merge and integrate when you talk about business but the actual act is the same - Incorporate can be used as an adjective while all three of them are verbs. Hope this helps Jane :)