write

[address] w[!] [[>>] file]

Write lines specified by address to file, or write full contents of buffer if address is not specified. If file is also omitted, save the contents of the buffer to the current filename. If >> file is used, write contents to the end of the specified file. Add a ! to force the editor to write over any current contents of file.

Example

:1,10w name_list		Copy first 10 lines to name_list
:50w >> name_list		Now append line 50