Sodium metal is typically used as the base to generate the alkoxide before treating with the alkyl halide.  
This reaction fails if tertiary halides are used, and works poorly with secondary halides since a competing E2 reaction may result.  Sodium metal is typically used as the base to generate the alkoxide before treating with the alkyl halide.  Resulting in an SN2 reaction, the first step involves the production of the alkoxide, a nucleophile that an alkyl halide in order to produce the namesake compound.  FTP, identify this organic chemistry reaction that produces ethers.
This reaction fails if tertiary halides are used, and works poorly with secondary halides since a competing E2 reaction may result.  
Williamson ether synthesis