The search command can be used to search the Stata site and other sites for Stata related information, including additional programs (.ado files), Stata FAQs, and other helpful web pages.  Its use is illustrated below.

Say that you read a web page or someone told you about a great program called nmissing that is not built into Stata, but can be downloaded over the internet.  You can search for this program from within Stata by typing

search nmissing

The Stata Viewer window appears, and we are shown a number of resources related to this keyword.  In the screen below, we see a partial listing starting with a FAQ and an example, and then SJ-15-4 (Stata Journal, Volume 15, Number 4) which has a recent version of this program you can download, and other Stata Journal articles which have an older versions of this program.

If we scroll down even further, we see another version from fmwww.bc.edu.  This is the Statistical Software Components site, which is the premier Stata download site for user-written Stata .ado files and often has the most up-to-date versions of .ado files.

If we click on that link, we get a window that shows us information about the program and a link that allows us to download the program.  We can also see that a help file comes with the program.  It is in blue, which  means that you can click on it to read the help file.  For some programs, you may want to do this before you download the program.

If you happen to have an earlier version of the program, you will be asked if you want to abandon the download or if you want to continue and force the installation, overwriting your existing version of the program.

Once you have downloaded the program, it is part of Stata and you can use it like any other command.  In this case, we could then type help nmissing to learn more about how to use it.

For more information on similar commands, see the help or reference manual about the search command