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shared vs. dedicated
If I want to sell things online, should I get a dedicated server rather than a shared server, or doesn't it matter?
It really depends on the traffic/success of your website. I think the solution for a small-medium sized business would be VPS hosting (between a shared hosting plan and a dedicated server).
A dedicated server is probably overkill for a starting e-commerce business. So when your business is booming and the time comes where a VPS server isn't enough, you can easily upgrade to a dedicated server in the future.