soup.select('div')
All elements named 


soup.select('#author')
The element with an id attribute of author

soup.select('.notice')
All elements that use a CSS class attribute named notice

soup.select('div span')
All elements named  that are within an element named 


soup.select('div > span')
All elements named  that are directly within an element named 
, with no other element in between

soup.select('input[name]')
All elements named  that have a name attribute with any value

soup.select('input[type="button"]')
All elements named  that have an attribute named type with value button