A computer is a machine capable of executing a program, literally “written in advance,” that is, a series of operations. This program is stored in a memory, and a processor performs the services. These operations act on data, which is also stored in the memory.CPU (Central Processing Unit): the processor. He controls the whole system. It can do necessary arithmetic calculations (addition, subtraction, multiplication) but only on integers, logical operations (and, or, complement), and test whether the result of these calculations is positive, negative or zero. He can read a number in memory or a port, or write it (via the bus). Two quantities characterize the CPU:
- The size of the accumulator (8, 16, 32, 64 bits): this is the maximum number of digits of a calculation (in binary). But an 8-bit processor can do 32-bit calculations; it just needs to do the math (so put four times more time)
- Its frequency: it is the number of elementary operations that it can do to the second. Quartz sends tops at regular intervals, at this frequency, which will allow timing calculations and synchronize the exchange of information between the different components.
How to recover deleted photos under Windows 10?
You can now undelete photos and recover deleted photos Windows 10 with Recoverit . It can scan each cell of the hard drive and retrieve the lost data. There are indeed ways to recover lost photos in Windows 10. Before you introduce the method, I explain how photos are deleted. When you remove a file, you first delete the file directory, including the file identification and the path. This is the reason why you can not access the deleted file. However, the original data of the data is not removed. They also exist in the storage medium. It is then possible to find deleted photos. If deleted photos are moved to the Recycle Bin, you can restore photos from the Recycle Bin under Windows 10. But if the pictures do not exist in the Recycle Bin or you empty the Recycle Bin, you need to prepare professional data recovery software, Recovering tools.
Note :Previously to the recovery of your deleted photos, you can not type new data on disc D, from which you want to find the images. After deletion, the spaces occupied by the deleted data are noticed available. Once new data is entered, the deleted data will be overwritten. You will not be able to recover back the deleted photos. So, do not open files after deletion.
First and foremost, you need to prepare data recovery software, such as recoverit tool. It is a tool designed to recover deleted pictures from an internal or external hard drive, memory card, camera, and Android phone. In addition to data recovery, you can find Office documents, videos, programs, and other types of files. After analyzing the hard drive with recoverit, you can preview the recovered photos and then retrieve them.
Central memory: it is divided into two parts:
- The random access memory ( RAM Random Access Memory) can be stored there (write) binary numbers to review them later. There are static memories ( SRAMs ) that memorize names as long as they are powered, and dynamics ( DRAMs ) that are faster but need to be rewritten at regular intervals. But all forget everything as soon as you cut the diet
- the read-only memory (ROM, Read Only Memory): these are components for manufacturing will always give the same values (5V or 0V). Even after the power failure. However, it is impossible to modify these values. There are now programmable ROMs ( PROMs ) that can be written, at one time, out of the computer, using a particular device (PROM programmer). Some can be reset to be rewritten at one time (EPROM, Erasable PROM)
The interfaces: the CPU sees them as memory, it can write to or read binary numbers. They allow the motherboard to interact with external devices called ” peripherals.” In general, the interface is implemented by an electronic card, which receives commands from the CPU, processes them and makes the answer if necessary.
Moreover, to void having to give binary commands to the computer, a program called the operating system ( OS ) was created for each machine, which is started when the computer starts up. He must know how to access the interfaces, wait for him to be given orders (we say launching a rule) and manages to execute them. In the beginning, the OS was machine specific, sold and maintained by the computer manufacturer. It only supported devices from the same manufacturer (and no way to exchange a BULL console with an IBM for example). Some academics, tired of having to rewrite the programs for all the OS, wrote a cross-platform OS (Multics then UNIX), but for a long time, the manufacturers refused to implement it, even to use UNIX it was necessary to buy the OS of the manufacturer.