Perspective distortion can be a tricky subject to understand; luckily it is easier to see than explain. It is directly related to the distance between the subject and the camera. The distortion occurs from trying to take a 3-D world and mapped it into a 2-D plane in the camera.
If you take a photo of a plate of food using a wide lens like a 28mm lens and then take a similarly framed photo using a 200mm lens, the two photos will be slightly different. In order to have the the plate of food fill the same amount of the frame, you have to get much closer using a 28mm lens. This is because the 28mm lens does not “zoom in” as much, but instead captures a wider angle field of view than a 200mm lens. While the plate of food will fill the same portion of the frame, the wider angle will include more of the objects around the plate and include more of the table.
Being close to the plate also introduces some distortion. Objects that are closer appear to be much larger than objects which are only slightly farther away. The result is that the distance between objects on the table gets distorted. The plate that is the subject of the photo appears to be very prominent while a candle further down the table would appear to be smaller and more distant than it actually is. This effect can useful if you are trying to place a special emphasis on the plate of food.
The illustration above shows the different camera positions that are needed to capture a similar photo using a zoom lens and a wide angle lens. With the wider angle lens on the right, more of the area surrounding the place setting gets captured in the photo because the lens has a wider field of view. In order to have the place setting fill as much of the frame with the wider angle lens, the camera has to be much closer.
The following photos show the difference distance makes and the effect of perspective distortion. Each photo is composed the same with the cutting board filling the bottom of the frame. It starts with the lens set at 135mm and goes down to 28mm, with each photo getting closer to the cutting board. Notice how the lines of the table and the sides of the cutting board converge together more dramatically as the camera gets closer. The last photo shows a comparison of this. The important thing to remember is that there is no correct approach, it is just important to be aware of perspective distortion so you can better achieve the look you are going for.