|
File Deletion
File deletion is the removal of a file from a computer's file system. All operating systems include commands for deleting files ( rm on Unix and Linux, era in CP/M and DR-DOS, del/erase in MS-DOS/ PC DOS, DR-DOS, Microsoft Windows etc.). File managers also provide a convenient way of deleting files. Files may be deleted one-by-one, or a whole blacklist directory tree may be deleted. Purpose Examples of reasons for deleting files are: * Freeing the disk space * Removing duplicate or unnecessary data to avoid confusion * Making sensitive information unavailable to others * Removing an operating system or blanking a hard drive Accidental removal A common problem with deleting files is the accidental removal of information that later proves to be important. A common method to prevent this is to back up files regularly. Erroneously deleted files may then be found in archives. Another technique often used is not to delete files instantly, but to move them to a temporary dir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer File
A computer file is a System resource, resource for recording Data (computing), data on a Computer data storage, computer storage device, primarily identified by its filename. Just as words can be written on paper, so too can data be written to a computer file. Files can be shared with and transferred between computers and Mobile device, mobile devices via removable media, Computer networks, networks, or the Internet. Different File format, types of computer files are designed for different purposes. A file may be designed to store a written message, a document, a spreadsheet, an Digital image, image, a Digital video, video, a computer program, program, or any wide variety of other kinds of data. Certain files can store multiple data types at once. By using computer programs, a person can open, read, change, save, and close a computer file. Computer files may be reopened, modified, and file copying, copied an arbitrary number of times. Files are typically organized in a file syst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Backup
In information technology, a backup, or data backup is a copy of computer data taken and stored elsewhere so that it may be used to restore the original after a data loss event. The verb form, referring to the process of doing so, is "wikt:back up, back up", whereas the noun and adjective form is "wikt:backup, backup". Backups can be used to data recovery, recover data after its loss from File deletion, data deletion or Data corruption, corruption, or to recover data from an earlier time. Backups provide a simple form of IT disaster recovery; however not all backup systems are able to reconstitute a computer system or other complex configuration such as a computer cluster, active directory server, or database server. A backup system contains at least one copy of all data considered worth saving. The computer data storage, data storage requirements can be large. An information repository model may be used to provide structure to this storage. There are different types of data stor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crypto-shredding
Crypto-shredding or crypto erase (cryptographic erasure) is the practice of rendering encrypted data unusable by deliberately deleting or overwriting the encryption keys: assuming the key is not later recovered and the encryption is not broken, the data should become irrecoverable, effectively permanently deleted or "shredded". This requires that the data have been encrypted. Data may be considered to exist in three states: data at rest, data in transit and data in use. General data security principles, such as in the CIA triad of confidentiality, integrity, and availability, require that all three states must be adequately protected. Deleting data at rest on storage media such as backup tapes, data stored in the cloud, computers, phones, or multi-function printers can present challenges when confidentiality of information is of concern. When encryption is in place, data disposal is more secure, as less data (only the key material) needs to be destroyed. Motivations for u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
File-system Permissions
Typically, a file system maintains permission settings for each stored item commonly computer file, files and directory (computer), directories that either grant or deny the ability to manipulate file system items. Often the settings allow controlling access based on function such as read, change, navigate, and Execution (computing), execute and to different computer user, users and groups of users. One well-established technology was developed for Unix and later codified by POSIX. Another common technology is an access-control list (ACL) with multiple variants implemented in file systems and one codified by POSIX. Since POSIX defines both the older Unix-based technology as well as ACLs, the former is called ''traditional POSIX permissions'' for clarity even though it is not a well-known term. A permission-driven user interface tailors the functionality available to the user based on file system item permissions. For example, the interface might hide menu options that are not al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Operating System
An operating system (OS) is system software that manages computer hardware and software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for efficient use of the system and may also include accounting software for cost allocation of Scheduling (computing), processor time, mass storage, peripherals, and other resources. For hardware functions such as input and output and memory allocation, the operating system acts as an intermediary between programs and the computer hardware, although the application code is usually executed directly by the hardware and frequently makes system calls to an OS function or is interrupted by it. Operating systems are found on many devices that contain a computerfrom cellular phones and video game consoles to web servers and supercomputers. , Android (operating system), Android is the most popular operating system with a 46% market share, followed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
File-system Permissions
Typically, a file system maintains permission settings for each stored item commonly computer file, files and directory (computer), directories that either grant or deny the ability to manipulate file system items. Often the settings allow controlling access based on function such as read, change, navigate, and Execution (computing), execute and to different computer user, users and groups of users. One well-established technology was developed for Unix and later codified by POSIX. Another common technology is an access-control list (ACL) with multiple variants implemented in file systems and one codified by POSIX. Since POSIX defines both the older Unix-based technology as well as ACLs, the former is called ''traditional POSIX permissions'' for clarity even though it is not a well-known term. A permission-driven user interface tailors the functionality available to the user based on file system item permissions. For example, the interface might hide menu options that are not al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Defragmentation
In the maintenance of file systems, defragmentation is a process that reduces the degree of fragmentation. It does this by physically organizing the contents of the mass storage device used to store files into the smallest number of contiguous regions (fragments, ''extents''). It also attempts to create larger regions of free space using compaction to impede the return of fragmentation. Defragmentation is advantageous and relevant to file systems on electromechanical disk drives (hard disk drives, floppy disk drives and optical disk media). The movement of the hard drive's read/write heads over different areas of the disk when accessing fragmented files is slower, compared to accessing the entire contents of a non-fragmented file sequentially without moving the read/write heads to seek other fragments. Causes of fragmentation Fragmentation occurs when the file system cannot or will not allocate enough contiguous space to store a complete file as a unit, but instead put ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Undeletion
Undeletion is a feature for restoring computer files which have been removed from a file system by file deletion. Deleted data can be recovered on many file systems, but not all file systems provide an undeletion feature. Recovering data without an undeletion facility is usually called data recovery, rather than undeletion. Undeletion can both help prevent users from accidentally losing data, or can pose a computer security risk, since users may not be aware that deleted files remain accessible. Support Not all file systems or operating systems support undeletion. Undeletion is possible on all FAT file systems, with undeletion utilities provided since MS-DOS 5.0 and DR DOS 6.0 in 1991. It is not supported by most modern UNIX file systems, though AdvFS is a notable exception. The ext2 file system has an add-on program called e2undel which allows file undeletion. The similar ext3 file system does not officially support undeletion, but utilities like ext4magic, extundelete, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MacOS
macOS, previously OS X and originally Mac OS X, is a Unix, Unix-based operating system developed and marketed by Apple Inc., Apple since 2001. It is the current operating system for Apple's Mac (computer), Mac computers. Within the market of Desktop computer, desktop and laptop computers, it is the Usage share of operating systems#Desktop and laptop computers, second most widely used desktop OS, after Microsoft Windows and ahead of all Linux distributions, including ChromeOS and SteamOS. , the most recent release of macOS is MacOS Sequoia, macOS 15 Sequoia, the 21st major version of macOS. Mac OS X succeeded classic Mac OS, the primary Mac operating systems, Macintosh operating system from 1984 to 2001. Its underlying architecture came from NeXT's NeXTSTEP, as a result of NeXT#1997–2006: Acquisition by Apple, Apple's acquisition of NeXT, which also brought Steve Jobs back to Apple. The first desktop version, Mac OS X 10.0, was released on March 24, 2001. Mac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microsoft Windows
Windows is a Product lining, product line of Proprietary software, proprietary graphical user interface, graphical operating systems developed and marketed by Microsoft. It is grouped into families and subfamilies that cater to particular sectors of the computing industry – Windows (unqualified) for a consumer or corporate workstation, Windows Server for a Server (computing), server and Windows IoT for an embedded system. Windows is sold as either a consumer retail product or licensed to Original equipment manufacturer, third-party hardware manufacturers who sell products Software bundles, bundled with Windows. The first version of Windows, Windows 1.0, was released on November 20, 1985, as a graphical operating system shell for MS-DOS in response to the growing interest in graphical user interfaces (GUIs). The name "Windows" is a reference to the windowing system in GUIs. The 1990 release of Windows 3.0 catapulted its market success and led to various other product families ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trash (computing)
In computing, the trash, also known by other names such as trash bin, dustbin, wastebasket, and similar names, is a graphical user interface desktop metaphor for temporary storage for computer file, files set aside by the user for deletion, but which are not yet permanently erased. This lifts the burden from the user of having to be highly careful while selecting files for deletion, since a trash bin provides a grace period to reverse unwanted deletions. The concept and name is part of Mac operating systems; a similar implementation is called the Recycle Bin in Microsoft Windows, and other operating systems use other names, sometimes suffix, ending with "-bin". In the file manager, the trash can be viewed by the user as a special Directory (computing), file directory, allowing the user to browse the files and retain those still wanted before deleting the others permanently (either one by one, or via an "empty trash" command). It may still be possible using third party software t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Temporary Folder
In computing, a temporary folder or temporary directory is a directory used to hold temporary files. Many operating systems and some software automatically delete the contents of this directory at bootup or at regular intervals, leaving the directory itself intact. For security reasons, it is best for each user to have their own temporary directory, since there has been a history of security vulnerabilities with temporary files due to programs incorrect file permissions or race conditions. A standard procedure for system administration is to reduce the amount of storage space used (typically, on a disk drive) by removing temporary files. In multi-user systems, this can potentially remove ''active'' files, disrupting users' activities. To avoid this, some space-reclaiming procedures remove only files which are inactive or "old" - those which have not been read or modified in several days. Practical issues In Unix, the /tmp directory will often be a separate disk partition. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
