How to define custom layout in magento like 1column,2-column right,3-columns

template/page/2columns-aboutus.phtml

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layout/page.xml

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find All Two-Column Layout Pages (Left Column) and place

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All Two-Column Layout Pages (About us Column)



1

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now define global object in xml

app/code/local/companyname/modulename/etc/config.xml

2 columns with About Us

page_two_columns_aboutus

Now go to admin login pages/ -----> 2 columns with About Us