A website is navigated automatically in a sequential manner, for example by performing a series of specific network requests in a specified order, without necessarily using a browser, and without necessarily rendering each web page in the sequence. Interactions with a website are automatically recorded, stored, and analyzed. Requests and responses can be associated with particular input/output operations. Based on the analysis, the system can determine what data is expected by web servers, so that it can effectively simulate browser operations in connection with those web servers, and extract useful information from the data received in response to those operations. Thus, data extraction and/or other operations can be performed more efficiently and more quickly, while reducing the computing resources needed.