In terms of growing awareness of the environmental impact of computing, green technology is gaining increasing importance. With the increase in energy consumption, global warming and electronic waste, the idea of ​​green computing is widely taken into serious consideration by both government agencies and private companies as their contribution to best practices for sustainable development. Green computing refers to the practice of responsible and environmentally efficient use of computing resources, while maintaining economic profitability and improving performance in an environmentally friendly manner. This paper aims to present the main approaches and hypotheses of green IT by showcasing the latest solutions and energy efficiency practices in the IT sector. This article has carried out a systematic study on different strategies and developments in the context of the sustainability of ICT as a future growth resource for modern society. Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get an original essay The article focuses on practices such as use, disposal, design and production, as well as technology-based solutions such as electronic products and services, for example eco-friendly cloud. Prospects for greener ICT should include the use of the Internet as a powerful agenda for promoting and educating environmentally conscious behavior and as a useful tool for creating eco-friendly technology. Keywords: Green computing, energy management, sustainability, green technology, green cloudI. IntroductionGreen computing is the term that refers to the efficient use of resources in computing and IT/IS infrastructure. Green computing efficiency places emphasis on minimizing hazardous environmental impact along with achieving economic feasibility and improving system performance. The field of “green technology” covers a wide range of topics: from alternative techniques of energy generation and electricity consumption and the use of environmentally friendly and recyclable materials to the implementation of sustainable digital services. Green technology technical issues include: green infrastructure (energy efficient buildings, smart cooling systems, renewable energy sources), green hardware (multicore computing systems, energy efficient server design, and state storage solid and green software and applications - parallelizing computational science algorithms to run on modern energy-efficient multi-core clusters, intelligent load distribution and CPU shutdown Nowadays, to achieve social awareness and promotion of green technological solutions, four main complementary approaches are used: • Green use: reduce the energy consumption of. computers, information systems and related peripheral subsystems in an environmentally friendly manner • Green disposal: renovation and reuse of existing and other old computers associated electronic devices. Recycling of unwanted used computers and other electronic waste by IT suppliers using their "take back" policy in order to take responsibility for the entire life cycle of the products they produce. • Green Design: in a broader aspect that connects companies, government agencies and environmental organizations in order to develop inventive management, business and regulatory processes that can improve environmental quality while strengthening economic development. and practical aspect of planningof energy-efficient and environmentally friendly computers and their subsystems such as servers and cooling equipment. • Green Manufacturing: The manufacturing process for computers and associated devices includes biodegradable manufacturing methods and components for little or no impact on the environment. This approach helps deliver economic benefits such as long-term cost savings and business process efficiency improvements. II. Green production In order to achieve the goals set by the idea of ​​ICT sustainability, it is necessary to take into account the entire process of creating the ICT infrastructure. Minimal impact on the environment should be one of the key assumptions for IT manufacturers during the design and production process of all ICT components. Leading IT companies are already applying green standards to their operations in order to: gain new revenue opportunities and promote social and environmental responsibility by influencing customers and competition in the market. The main areas of green computer manufacturing are: computing resources that meet the stringent restrictions of, for example, Energy Star that allow further use with certain power and energy management requirements (including special modes and permissions). “Energy Star devices can be programmed to turn off at a low electrical level when not in use, helping to save energy and run cooler, which helps them last even longer.”• Using bio-based materials: Materials Biodegradable and renewable often require less energy to produce than traditional toxic materials. Manufacturers use many different types of plastic in computers, which makes recycling very volatile. Furthermore, computers contain contaminants that are dangerous for the environment such as: cadmium, lead, mercury or chromium. The use of harmful energy-consuming materials can be replaced by efficient and recyclable elements, for example displays made with OLEDs (organic light-emitting diodes): no mercury is used in production, making them more environmentally friendly . III. Green usage The great importance is to understand the entire life cycle of computing resources, while applying the idea of ​​green computing. Below are areas and practices that users can implement to maximize utility and minimize negative consequences for the environment: • PC power management techniques: Set of actions and mechanisms to control hardware power consumption of the personal computer, mainly by turning off the power or switching the system to the low power state when idle. In computing, this type of energy management is based on the specification called Advanced Configuration and Power Interface (ACPI), an open industrial standard that allows direct control and management of energy savings by the operating system - automatic shutdown of the monitor, standby. by mode, etc. Also, the system can go into hibernation, at a time when the CPU and RAM are disabled. Some software solutions allow voltage definition, for example on the CPU, which helps reduce heat production and power consumption. Some mobile processors can adjust the voltage to the capacity required at any given time. This technology is called Speed ​​​​Stepon Intel, Power Now! • Virtualization: In traditional IT infrastructure, servers are dedicated to specific computing functions such as storage, communication, databases, and so on. Virtualization eliminates the need for a dedicated server to run applications: at the same time, it allows you to run multiple operating systems on the same onehardware platform and the system at the highest possible performance. It is based on launching the operating system in a virtual machine, abandoning the universality of emulation of many computer architectures. Limitation only to the hardware platform used to run a certain number of guest operating system processes (emulated system) directly on the computer hardware. Only when these operations are not performed directly does the virtualizer emulate them. This means that a virtualizer boots the operating system so that it can coexist with the primary system and achieve maximum compatibility and performance. Dedicated servers are only used when there are active connections, they can be used for other purposes during their idle or inactive time or use. Virtualization contributes to green technology on the one hand by reducing the number of servers, desktop power and disposal requirements and by limiting expensive business travel of staff, customers and suppliers, as well as by replacing paper-based systems with online communication platforms. IV. GreenDisposalThe green technology disposal approach includes the refurbishment and reuse of old, existing computer equipment and the proper recycling of obsolete, unwanted, or broken computers and their subsystems. Due to the strength of the negative environmental effects resulting from an improper approach to disposal, this aspect of green computing is among the most important: • Reuse: Even old computers should continue to be used as long as they meet user requirements. IT systems whose basic functions are obsolete and do not meet the owner's needs can be transferred to anyone who wants to use it or needs it for its functional components. Many charities and non-profit organizations are willing to receive old equipment through donations to repurpose it or use its particular function. Prolonged use of a computer system contributes significantly to the reduction of negative environmental effects. • Refurbishment: By refurbishing and replacing IT hardware parts, the user can prolong their use. Old equipment can be restored while maintaining its functions; It can also be updated to gain new functionality. The reasons for such actions can be motivated by the lower cost of refurbished equipment: nowadays more and more companies are willing to purchase refurbished hardware and this market is growing. At this point it is important to understand the difference between a "refurbished" and a "used" product. Refurbishing gives the guarantee that the product has been tested and verified to work correctly while "used" products may or may not be defective. Hardware vendors often resell equipment returned under warranty after repairing defects and verifying proper operation. Refurbished hardware provides a cost-effective alternative. Another incentive could be maintaining company standards by ensuring that all employees use the same equipment. This action significantly reduces electronic waste. • Recycling: Recycling is one of the most complex methods of environmental protection. Its goal is to reduce the consumption of natural resources and reduce waste. The principle of recycling is to maximize the reuse of materials, taking into account the minimization of costs for their processing. This principle allows you to protect both the raw materials necessary for production and those necessary for subsequent processing. Recycling occurs in two areas: the production of products and the subsequent waste formation of these goods. The recycling hypotheses imply the imposition ofappropriate attitudes among producers of goods, favoring production with the most recoverable materials and creating appropriate behavior on the part of the recipients of these goods. E-waste from computers and associated equipment contains various substances, many of which are dangerous, such as mercury, cadmium, lead, arsenic and chromium. The health effects of these toxins on humans include birth defects, damage to the brain, heart, liver, kidneys, skeleton, reproductive and nervous systems. If computers are thrown into landfills or other inappropriate places, toxic chemicals can be released into the environment (food chain and water). Another threat is the burning of e-waste, which causes the release of a toxic gas into the air we breathe. Although e-waste mainly contains harmful materials, you can find some precious metals such as gold and copper which become the source of secondary raw materials. Such actions can be turned into profitable businesses. To summarize: “the production and purchase of energy-efficient IT infrastructure, the efficient operation and use of computing devices, as well as their correct disposal, i.e. environmentally friendly production, use and disposal are the efforts which lead to economic and ecological benefits”.V. latest developments Green Cloud ComputingThe May 2009 Gartner report defines the concept of cloud as “a style of computing in which scalable and elastic IT capabilities are provided as a service to multiple customers using Internet technologies”. The understanding in three dimensions: economic, environmental and social. Clouds consolidate your environment, saving energy, cooling, space and money. Cost savings and operational flexibility are among the most frequently cited benefits associated with the decision to adopt cloud computing. The fixed costs linked to infrastructure investments are reduced (which in the traditional business model generally increase with time and the need to update the software), as well as the energy costs that power the infrastructures. Traditional costs related to licenses, number of users, equipment, operation, repairs and applications are replaced by paying for the functionality actually used by the company or other organization that also gets access to the latest technology. This solution allows you to adapt supply to demand, eliminating unnecessary costs associated with overestimating or underestimating customer needs. At the same time, it affects the reduction of the risk of lost sales opportunities and costs resulting from incorrect demand forecasting and supply planning by the company. Some aspects of the cloud ICT infrastructure allow the model to be identified as one that can be achieved in an environmentally friendly way by migrating IT resources to the cloud. These aspects can include: • Dynamic provisioning and multi-tenancy: lower energy consumption and associated carbon emissions compared to the traditional over-provisioning approach. Automatic processing of the computing environment supports user needs, operating in the cloud can acquire or release resources (instances) where appropriate (based on demand). Dynamic resource allocation is done automatically, so data centers keep servers active based on current demand. With virtualization technology, which allows you to connect disparate resources into one large pool of resources, you can release them more selectively to all customers while increasing the level of their usage. Without virtualization, cloud computing would never have been born. The whole.