Best Lenses For Canon Dslr Camera

Paul asks…How do you know what camera would be good for taking pictures with blurry backgrounds?I'm looking to get a good black friday deal on a camera. I want to be able to take some nice portraits with blurry backgrounds...I know you have to have a low aperature number but I don't know much beyond that. the camera I have now isn't very good even on the lowest aperature setting. What do I look for to tell if a camera would be good for taking blurry background photos? I also what to use it

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