{"id":22701,"date":"2021-11-02T11:11:01","date_gmt":"2021-11-02T11:11:01","guid":{"rendered":"https:\/\/ded9.com\/?p=22701"},"modified":"2025-11-03T11:26:46","modified_gmt":"2025-11-03T11:26:46","slug":"what-is-bios-basic-input-output-system","status":"publish","type":"post","link":"https:\/\/ded9.com\/de\/what-is-bios-basic-input-output-system\/","title":{"rendered":"What Is BIOS (Basic Input\/Output System)? \u2014 An Essential Guide"},"content":{"rendered":"<p><span data-preserver-spaces=\"true\">BIOS (basic input\/output system) is the program a computer&#8217;s microprocessor uses to start the computer system after it is powered on. It also manages data flow between the computer&#8217;s operating system (OS) and attached devices, such as the hard disk, video adapter, keyboard, mouse, and printer.<\/span><\/p>\n<h2><span data-preserver-spaces=\"true\">History of BIOS: basic input\/output system<br \/>\n<\/span><\/h2>\n<p><span data-preserver-spaces=\"true\">BIOS was first coined in 1975 by American computer scientist Gary Kildall. It was incorporated into IBM&#8217;s first personal computer in 1981 and, in the years to come, gained popularity within other PCs, becoming an integral part of computers for some time. However, BIOS&#8217; popularity has waned in favor of a newer technology: Unified Extensible Firmware Interface (UEFI). Intel announced a plan in 2017 to retire support for legacy BIOS systems by 2020, replacing them with UEFI.<\/span><\/p>\n<h2><span data-preserver-spaces=\"true\">What are the factors that make up BIOS?<\/span><\/h2>\n<p><span data-preserver-spaces=\"true\">The BIOS includes instructions on how to load basic computer hardware. It also consists of a <a href=\"https:\/\/en.wikipedia.org\/wiki\/Power-on_self-test\" target=\"_blank\" rel=\"noopener\">POST<\/a> (Power-On Self-Test) test that helps verify the computer meets the requirements to boot up properly. If the computer does not pass the POST, you hear a combination of beeps indicating what is malfunctioning.<\/span><\/p>\n<h2><span data-preserver-spaces=\"true\">Uses of BIOS<\/span><\/h2>\n<p><span data-preserver-spaces=\"true\">The primary use of BIOS is to act as a middleman between OSes and the hardware they run on. BIOS is theoretically always the intermediary between the microprocessor and the I\/O device to control information and data flow. In some cases, BIOS can arrange for data to flow directly to memory from devices, such as video cards, which require faster data flow to be effective.<\/span><\/p>\n<h2><span data-preserver-spaces=\"true\">How does the BIOS function?<\/span><\/h2>\n<p><span data-preserver-spaces=\"true\">As we said above, BIOS\u00a0 (basic input\/output system) comes with computers, as firmware on a chip on the motherboard. In contrast, an OS like Windows or iOS can either be pre-installed by the manufacturer or vendor or installed by the user. BIOS is a program made accessible to the microprocessor on an erasable programmable read-only memory (EPROM) chip. When users turn on their computer, the microprocessor passes control to the BIOS (basic input\/output system)\u00a0 program, which is always located at the same place on an EPROM.<\/span><\/p>\n<p><span data-preserver-spaces=\"true\">When a BIOS boots up a computer, it first determines whether all necessary attachments are operational. Any hardware containing files that the computer needs to start is called a <\/span><em><span data-preserver-spaces=\"true\">boot device<\/span><\/em><span data-preserver-spaces=\"true\">. In addition, after testing and ensuring boot devices are functioning, BIOS loads the OS &#8212; or key parts of it &#8212; into the computer&#8217;s random access memory (RAM) from a hard disk or diskette drive (the boot device).<\/span><\/p>\n<h2><span data-preserver-spaces=\"true\">What are the four main functions of a BIOS?<\/span><\/h2>\n<p><span data-preserver-spaces=\"true\">BIOS identifies, configures, tests, and connects computer <a href=\"https:\/\/ded9.com\/hardware-and-software\/\">hardware<\/a> to the OS immediately after a computer is turned on. The combination of these steps is called the <\/span><em><span data-preserver-spaces=\"true\">boot process<\/span><\/em><span data-preserver-spaces=\"true\">.<\/span><\/p>\n<p><span data-preserver-spaces=\"true\">These tasks are each carried out by BIOS&#8217; four main functions:<\/span><\/p>\n<ul>\n<li><strong><span data-preserver-spaces=\"true\">Power-on self-test (POST).<\/span><\/strong><span data-preserver-spaces=\"true\"> This tests the computer&#8217;s hardware before loading the OS.<\/span><\/li>\n<li><strong><span data-preserver-spaces=\"true\">Bootstrap loader.<\/span><\/strong><span data-preserver-spaces=\"true\">\u00a0This locates the OS.<\/span><\/li>\n<li><strong><span data-preserver-spaces=\"true\">Software\/drivers.<\/span><\/strong><span data-preserver-spaces=\"true\">\u00a0This locates the software and drivers that interface with the OS once running.<\/span><\/li>\n<li><strong><span data-preserver-spaces=\"true\">A complementary metal-oxide-semiconductor (CMOS) setup<\/span><\/strong><span data-preserver-spaces=\"true\">\u00a0is a configuration program that allows users to alter hardware and system settings. CMOS is the name of the BIOS&#8217; non-volatile memory.<\/span><\/li>\n<\/ul>\n<h2><strong><span data-preserver-spaces=\"true\">Features of BIOS<\/span><\/strong><\/h2>\n<ul>\n<li><span data-preserver-spaces=\"true\">\u00a0Access<\/span><\/li>\n<li><span data-preserver-spaces=\"true\">\u00a0security<\/span><\/li>\n<li><span data-preserver-spaces=\"true\">manufacturers<\/span><\/li>\n<\/ul>\n<h3><span data-preserver-spaces=\"true\">BIOS access<\/span><\/h3>\n<p><span data-preserver-spaces=\"true\">With BIOS, the OS and its applications are freed from having to understand exact details, such as computer hardware addresses, about the attached I\/O devices. When device details change, only the BIOS program needs to be changed. Sometimes, this change can be made during system setup.<\/span><\/p>\n<p><span data-preserver-spaces=\"true\">Users can access BIOS and configure it through the BIOS Setup Utility. Accessing the BIOS Setup Utility varies somewhat depending on the computer being used. However, the following steps generally enable users to access and configure BIOS through the Setup Utility:<\/span><\/p>\n<ul>\n<li><span data-preserver-spaces=\"true\">Reset or power off the computer.<\/span><\/li>\n<li><span data-preserver-spaces=\"true\">When the computer turns back on, look for a message that says &#8220;entering setup&#8221; or a similar message. Accompanying that message will be a key that the user should press to enter the system configuration. For example, a user might see an example message: &#8220;Press [key] to enter BIOS setup.&#8221; Some keys often used as prompts are Del, Tab, Esc, and any of the function keys (F1-F12).<\/span><\/li>\n<li><span data-preserver-spaces=\"true\">Upon seeing the prompt, quickly press the key specified.<\/span><\/li>\n<\/ul>\n<p><span data-preserver-spaces=\"true\">Once in BIOS Setup Utility, users can change hardware settings, manage memory settings, change the boot order or boot device, and reset the BIOS password, among other configuration tasks.<\/span><\/p>\n<h3><span data-preserver-spaces=\"true\">BIOS security<\/span><\/h3>\n<p><span data-preserver-spaces=\"true\">BIOS security is a somewhat overlooked component of cybersecurity; however, it should still be managed to prevent hackers from executing malicious code on the OS. In 2017, security group Cylance showed how modern BIOS security flaws could enable ransomware programs inside a motherboard&#8217;s UEFI and exploit other PC BIOS vulnerabilities.<\/span><\/p>\n<p><span data-preserver-spaces=\"true\">Another unique exploit involving the manipulation of the BIOS was Plundervolt. Plundervolt could be used to mess with a computer&#8217;s power supply when data was being written to memory, causing errors that led to security gaps. Intel released a BIOS patch to defend against it.<\/span><\/p>\n<h3><span data-preserver-spaces=\"true\">BIOS manufacturers<\/span><\/h3>\n<p><span data-preserver-spaces=\"true\">IBM originally owned BIOS. However, some companies, such as Phoenix Technologies, have reverse-engineered IBM&#8217;s original version to create their own. In doing this, Phoenix allowed other companies to create clones of the IBM PC and, more importantly, create non-IBM computers that work with BIOS. One company that did this was Compaq.<\/span><\/p>\n<p><span data-preserver-spaces=\"true\">Today, many manufacturers produce motherboards with BIOS chips. Some examples are the following:<\/span><\/p>\n<ul>\n<li><span data-preserver-spaces=\"true\">Hewlett-Packard (HP)<\/span><\/li>\n<li><span data-preserver-spaces=\"true\">Asus<\/span><\/li>\n<li><span data-preserver-spaces=\"true\">Foxconn<\/span><\/li>\n<li><span data-preserver-spaces=\"true\">AMI<\/span><\/li>\n<\/ul>\n<p><span data-preserver-spaces=\"true\">Knowing the motherboard manufacturer is important because users may want to update their BIOS and chipset drivers\u2014the drivers that enable the OS to work with other devices in the computer, such as a video card\u2014to the most recent versions. Driver updates may improve computer performance or patch recent BIOS-level security vulnerabilities. Each manufacturer has a unique way of updating these drivers.<\/span><\/p>\n<p><span data-preserver-spaces=\"true\">So let&#8217;s get acquainted with some questions related to BIOS<\/span><\/p>\n<h2><span data-preserver-spaces=\"true\">Can a BIOS chip be upgraded or updated?<\/span><\/h2>\n<p><span data-preserver-spaces=\"true\">Adding additional memory to a BIOS chip, as an upgrade, can only be done by replacing the existing BIOS chip with a new, more advanced BIOS chip.<\/span><\/p>\n<p><span data-preserver-spaces=\"true\">Also, the data on a BIOS chip can be updated if it&#8217;s a flash BIOS. Using specially designed software, the BIOS can be updated to fix problems or add new features to the motherboard.<\/span><\/p>\n<h2><strong><span data-preserver-spaces=\"true\">Conclusion<\/span><\/strong><\/h2>\n<p><span data-preserver-spaces=\"true\">Therefore, in this article, we discussed BIOS and its features, and we hope you learned something about it.<\/span><\/p>\n<h2>FAQ<\/h2>\n<div id=\"rank-math-rich-snippet-wrapper\"><div id=\"rank-math-faq\" class=\"rank-math-block\">\n<div class=\"rank-math-list \">\n<div id=\"faq-1\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question \">What is the BIOS and what does it do?<\/h3>\n<div class=\"rank-math-answer \">\n\n<p>BIOS (Basic Input\/Output System) is firmware stored on a chip on the motherboard that initializes hardware components and starts the boot process when a computer is turned on.<\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-2\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question \">How does BIOS differ from UEFI?<\/h3>\n<div class=\"rank-math-answer \">\n\n<p>BIOS is older and uses a text-based interface with limitations like support for MBR partitions, while UEFI is newer, supports larger drives, has a graphical interface, and offers enhanced security features.<\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-3\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question \">Can you update the BIOS, and is it safe?<\/h3>\n<div class=\"rank-math-answer \">\n\n<p>Yes, the BIOS can be updated (flashed) to improve compatibility or fix bugs, but it must be done carefully following manufacturer instructions to avoid system damage.<\/p>\n\n<\/div>\n<\/div>\n<\/div>\n<\/div><\/div>\n","protected":false},"excerpt":{"rendered":"<p>BIOS (basic input\/output system) is the program a computer&#8217;s microprocessor uses to start the computer system after it is powered on. It also manages data flow between the computer&#8217;s operating system (OS) and attached devices, such as the hard disk, video adapter, keyboard, mouse, and printer. History of BIOS: basic input\/output system BIOS was first [&hellip;]<\/p>\n","protected":false},"author":9,"featured_media":22703,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[1863],"tags":[33],"class_list":["post-22701","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-computer","tag-os"],"acf":[],"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/ded9.com\/de\/wp-json\/wp\/v2\/posts\/22701","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ded9.com\/de\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ded9.com\/de\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ded9.com\/de\/wp-json\/wp\/v2\/users\/9"}],"replies":[{"embeddable":true,"href":"https:\/\/ded9.com\/de\/wp-json\/wp\/v2\/comments?post=22701"}],"version-history":[{"count":5,"href":"https:\/\/ded9.com\/de\/wp-json\/wp\/v2\/posts\/22701\/revisions"}],"predecessor-version":[{"id":262750,"href":"https:\/\/ded9.com\/de\/wp-json\/wp\/v2\/posts\/22701\/revisions\/262750"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/ded9.com\/de\/wp-json\/wp\/v2\/media\/22703"}],"wp:attachment":[{"href":"https:\/\/ded9.com\/de\/wp-json\/wp\/v2\/media?parent=22701"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ded9.com\/de\/wp-json\/wp\/v2\/categories?post=22701"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ded9.com\/de\/wp-json\/wp\/v2\/tags?post=22701"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}