There are a few seemingly perpetual debates in web design. 800×600 vs 1024×768. Fixed vs fluid. Content on the right or left. The choice of using a 2 column layout or a 3 column one is another of these.
Advantages of a Two Column Layout
Forces minimalism. There tends to be less sidebar room in a 2 column layout. You simply don’t have the space for 100 different widgets without overstretching the page. This limit forces you to be a little more careful about choosing which widgets are installed.
Sidebar padding. In a 3 column layout, each of the two sidebar columns is rarely as wide as the one sidebar column in a 2 column layout. Some of the broader widgets tend to be feel cluttered in such an environment. 2 column layouts have a little more defense in this regard.
Advantages of a Three Column Layout
Sidebars take up more space. Whilst taking up less space can be an advantage, so too can taking up more space. When you have a lot of room to fill, and don’t want to stretch your content horizontally to do so, the extra sidebar width can be your saving grace.
Less cluttered feeling. Taking a set number of widgets and placing them vertically in a 2 column layout is one thing. If you then take those same widgets and spread them over the 2 sidebars in a 3 column layout, you will notice things tend to feel much less cluttered, when done well.
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