The wwwblast package contains a suite of standalone programs that perform various similarity searches using the BLAST heuristic algorithm. Similar to the NCBI BLAST server http://www.ncbi.nlm.nih.gov/blast/. wwwblast provides a graphic user interface (GUI) through the use of web forms. Individual program takes the user inputs from the web form and returns the search result to a browser window. There are different web forms for different BLAST programs. For example, 'Regular BLAST' is for running the traditional 'blastn/blastp/blastx/tblastn/tblastx' seraches. Various web forms incorporate commonly used BLAST parameters found in standalone commandline BLAST programs and the results are similar to, but not the same as, those obtained from the NCBI BLAST server.
The 'www' in the package name also refers to the requirements for using this package, i.e., it needs to be installed under the htdocs directory under an existing web server (Apache). This generally requires a Linux/Unix platform. NCBI does not provide binary for PC running Windows. The alternative is to use cygwin X-window emulation system http://www.cygwin.com/. which will require the recompilation of NCBI C++ toolkit under this environment to get the wwwblast related binaries.
The wwwblast package itself does not support any request queuing and load balancing. As soon as the user hits a "Search" button, BLAST will start immediately if entered information is valid. So, this server package is not intended to handle large load, which may exist in many public services. Also, wwwblast does not support distributed computation similar to the splitd system used by the NCBI BLAST server [1].