Key Difference: Apache refers to Apache http server developed by the Apache Software Foundation. It is an open source and free of cost server. Httpd stands for Hypertext Transfer Protocol Daemon. In reference to Apache, httpd refers to the Apache HyperText Transfer Protocol (HTTP) server program which handles the requests. Thus, both the terms are also used interchangeably.

Apache refers to Apache http server developed by the Apache Software Foundation. It is an open source and free of cost server. It is capable of supporting multiple platforms, including Linux, Windows, and Macintosh operating systems. It provides a range of features and many of them are implemented by using compiled modules. It provides password and digital certificate authentication.

Apache is efficient in serving static content at a fast rate. It provides numerous features like CGI, SSL and virtual domains. It supports numerous web programming languages like Perl, PHP and Python. It is highly portable and thus can be installed on different types of servers and operating system. It can work on any server with an Intel 80x86 series of processor when it is combined with Windows. Apache 2 also supports the Internet protocol IPv6.

Httpd stands for Hypertext Transfer Protocol Daemon. Daemon refers to a program that runs without break

and sends requested data to user. Each server of pages on the Web has an HTTPD or Hypertext Transfer Protocol daemon that waits for the requests from web clients and their users. Httpd with reference to Apache refers to the Apache HyperText Transfer Protocol (HTTP) server program. It has been constructed to be executed as a standalone daemon process. It creates a pool of child processes or threads in order to handle the requests.

Comparison between Apache and Httpd:

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