Why am I having conflicts during rebase when I am the only developer on my Github project?

I am new to Git and tried Github to learn the new source control system and I am wondering why am I having conflicts after a rebase or even a merge when I am the only one contributing to it. Since I am the only dev, shouldn’t my version of the source always be in ‘sync’ (no conflicts) with the one in Github?

Can you please explain to me what is causing the conflicts and if I can do something about it?

I am using egit in eclipse and my workflow is basically this.

edit => commit => rebase => push

P.S. I am only coding on one computer.

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