SOftware

LICENSURE

"End User License Agreement" (EULA) or a "Software License Agreement" ****serves as a contract between the licensor (e.g., software company) and the purchaser, indicating that the purchaser has a right to use the software NO ROOM FOR NEGOTIATION OPEN SOURCE software ::: may also come with an agreement license that specifies how it may be used FREE SOFTWARE::: GNUs Public License::: is used for free software -designed so that it will stay free regardless of who modifies the software COPYLEFT:::: Instead of using rights to limit users (as proprietary software does), it promotes freedom and flexibility of use. Creative Commons (CC) license::::: one of several public copyright licenses that enable the free distribution of an otherwise copyrighted work -used when an author wants to give people the right to share, use, and build upon a work that he/she has created

Cloud Computing

-ability to offload computation and storage from your local computer to the cloud Cloud computing combines several different technologies: distributed computing, computer networks, and storage area networks ANYTIME, ANYWHERE ACCESS and UNLIMITED SCALING To access a cloud= interface is made through a WEB PORTAL or through SPECIFIC APPLICATION DOWNLOAD and NEED ACCOUNT cloud is the ultimate in a client-server network Services offered by cloud computing range from simple storage to database and web services, e-mail, games, and load balancing for large-scale computational processing. ADVANTAGES: -increased processing power -software that they do not have licenses for on their local machine -storage in excess of their local file server or computer -allows an organization access to resources and applications from anywhere/anytime -less to invest in -allows for scaling -common platform leading to better standardization -decreased need for internal IT personnel

LAYERS OF OS

-user -applications -OS utilities (system software) -Services(system software) -Shells(system software) -OS Kernel (system software) -Software Device drivers(system software) -OM BIOS Drivers -Hardware KERNEL: core components of OS are reffered to as KERNEL -loads when computer is first booted -in the kernel are the components that handle process management, resource management, and memory management -Without these, cant start a new program or have that program run efficiently -sits on top of the hardware and is the interface between hardware and software

3 type of language translators

1. assembly languages, 2. high-level compiled languages 3. high-level interpreted languages The translators for these three types of languages are called assemblers, compilers, and interpreters, respectively.

Intranet

A LAN that uses the Internet Protocol is known as an INTRANET ***** ******private network that can only be accessed by authorized users -intranet is that applications intended for Internet usage (e-mail, web browsing, telnet/ssh, etc.) will work internally as easily as they work externally???? -include restrictions on access (user access) ex:any software application that an organization wishes to make available to its employees via the organization's LAN can utilize IP for managing comms btwn user and application THIS IS REFEREED TO AS AN INTRANET

Database Server

A structured data repository -DBMS: software that responds to user queries to get from the database -database servers permits database access across a network -can do: data analysis, manipulation, security, archiving -SOME CAN STORE DATABASE ITSELF -BUt, by seperating server from the databse. you can use different mechanisms to store the database ex: storage are netowork to support load balancing MySQL = opensource DB server MySQL community= DB server There is also a proxy server for a MySQL database, a cluster server for high-speed transactional database interaction, and a tool to support GUI construction.

Algorithms

An algorithm is a set of instructions used by a computer to execute a procedure **FORMULA, end result is a PROCESS for computer OR a set of steps that are followed in order to complete a computer process. HOW TO: In an algorithm, -the instructions must be clear so the rules are unambiguous -there must be a distinct stopping point.

binary (MACHINE LANG)

Computers store, transmit, and process all information in binary instead of decimal -because everything is stored in one of two ways, current or no current (1s or 0s) ON or OFF -BASE 2 SYSTEM = can represent any number with just two digits Every data, whether a number, text, a picture, a song, a movie, etc., is stored as a sequence of 1's and 0's *****The digital circuits in the CPU operate on bits and memory stores bits.************ -Today's computers typically provide 32 bits (4 bytes) or 64 bits (8 bytes) for the typical storage size. We refer to the typical storage size as the computer's word size. CAN TRANSLATE THEM INTO DIFFERENT REPRESENTATIONS: EX: octal

Copyleft

Copyleft is a play-on-words of copyright instead of using rights to limit users (as proprietary software does), it promotes freedom and flexibility of use.

Device Drivers

Device drivers provide specific interfaces between the OS running a computer and hardware Many device drivers are PRELOADED into the operating system, whereas others must be loaded off of the Internet or CD-ROM when a new hardware device has been purchased -There are literally hundreds of thousands of drivers available AND there is no need to fill a user's hard disk drive with all of them when most will never be used

FTP Server

FTP is like Web Server: both Host files and allow clients access to those files BUT FTP access is in form of uploading files and downloading files OLD, OLDER than HTTP -only use it for file uploadding -any downloaded files are saved to disk (webserver just requires files be loaded directly into clients web browser) -requires user account or the user to log in as anonymous user anon: access to public files (/pub) An FTP server is available in Linux, ftpd. This service is text-based. An extension to FTP is FTPS, a secure form of FTP although SFTP is another secure way to handle file transfer, it is not based on the FTP protocol Popular FTP client tools for performing FTP include WS-FTP and FileZilla, both of which are GUI programs that send commands to an FTP server. FileZilla can also operate as an FTP server, as can Apache

LICENSE USED FOR FREE SOFTWARE....

GNUs Public License is used for free software -designed so that it will stay free regardless of who modifies the software

Hexadecimal Number System (base 16)

In hexadecimal, we group 4-bit binary numbers and convert them to the equivalent hexadecimal digit. use this to translate binary system uses letters every value is represented with some combination of 16 digits (0-9 and A,B,C,D,E,F) - base 16.

LAN

LAN(local area network) where a collection of devices connected together in one physical location, such as a building, office, or home

COPYRIGHTS

Protects an original work (in its tangible, expressed form), but not the ideas behind the work most frequently used protection ON PUBLIC RECORD NEGATIVES: copyright law may be interpreted inconsistently and the protections may not be very strong -protect an original work (in its tangible, expressed form), but not the ideas behind the work PRIVILEGES: 1. copyright holder has the exclusive right to make copies, prepare derivative works, and distribute copies of the work for the duration of the author's life plus 70 years "Fair use" provides an exception to this by allowing nonprofits or educational institutions to use the copyrighted work.

SERVICES

Services, or daemons, are operating system programs that are usually started when the operating system is loaded and initialized, but they run in the background -the program, while it is active, does not take up any CPU time until it is called upon to do so

Shareware Software

Software permits free temporary use followed by long-term activation fee like a TRIAL VERSION before paying -YOU DONT GET A LICENSE UNTIL YOU PAY for full version PRIVILEDGES: 1. usually a set number of uses, a set number of days, or restrictions on the features -easily upgrade it to the full version by purchasing a registration license

UTILITY PROGRAMS

System utilities are programs that allow the user to monitor and improve system performance LARGE RANGE OF FUNCTIONS: EX:utilities exist to defragment the hard disk and to scan files for viruses and other forms of malware -Usually, system utilities must be installed separately as they may not come with the operating system (often, these require purchasing and so many users may ignore their availability)

Fair Use

The ability to use a small amount of copyrighted work without permission, but only in certain ways and in specific situations (schoolwork and education, news reporting, criticizing or commenting on something, and comedy/parody). "Fair use" provides an exception to this by allowing nonprofits or educational institutions to use the copyrighted work.

Proxy Server

Used in organization to act as a giant cache of web pages that anyone in the organization has recently viewed -if many ppl view the same pages often, CACHING these pages LOCALLY permits future access to be local rather than remote -also provides anonymity: IP address recorded by web server you are taking the page from records the proxy server IP -BLOCKS CONTENT from being returned. rejects requests going to specific servers (ex: PornHub) and rejects responses that contain certain content (ex: porn) -Squid and Apache most common proxy server BOTH ARE OPEN SOURCE system and web admin LOCAL> REMOTE access

Decimal : number system

When we have a number larger than 9 that we need to represent, we use a 2nd digit with each digit representing a power of 10. ex: 1456, we have 1 in the thousands position, 4 in the hundreds position, 5 in the tens position and 6 in the ones position BASE 10 system USES #s 1-10

language translators

a program that takes a high-level language program as input, and creates a machine-language program as output aka: programming languages =vocabulary and set of rules for instructing a computer to perform certain tasks. assembly language; instruction BASIC, C, C++, Java, and Python ex:BASIC, C, C++, Java, and Python

operating systems

a program whose primary task is to allow a user to easily access hard and software of the computer system -it MAINTAINS THE COMPUTERS ENVIRONMENT goal: CONTROL and CONVENIENCE for user btwn hardware and software GUI makes this easy Linux and Unix issue commands in two ways: 1. GUI 2. typing commands at a command line prompt -both Windows and Mac OS also have command line prompts available but not used as much as GUI

programming languages

a vocabulary and set of rules for instructing a computer to perform certain tasks there are scripting languages and programming languages Examples of high-level programming languages include, but are not limited to, Python, BASIC, C, C++, COBOL, FORTRAN, Ada, and Pascal -high level scripting language: python

OS: User vs admin

admin had OS control to: -create new users, test for holes in security, manipulate system files,etc TWO TYPES OF OS ACCOUNTS: 1. ADMIN: (aka: Root or Superuser account) *owner for all of the system software and some of the application software -windows calls this account: administrator - to log in, must log in as user or use "run as", and enter secret password few know -Linux: account called "root" -to log in, must use SU COMMANDS (switch user) or SUDO COMMAND to run under context of another user -"su' is usually used by saying "su username123" , then OS needs log in and password BUT, -if you dont type the uername part, you are requesting to to change to root (admin) -In Linux, an ls -l (long listing) of directories (such as /sbin, /bin, /usr/ bin, and /usr/sbin) will demonstrate that many of the programs and files are owned by root sometimes only root cat access them OR root can write to/execute but others can view ex:root runs 'useradd' so that sys admin can add user accounts linux: /root = homepage

KERNEL

core components of OS are reffered to as KERNEL -loads when computer is first booted -in the kernel are the components that handle process management, resource management, and memory management -Without these, cant start a new program or have that program run efficiently -sits on top of the hardware and is the interface between hardware and software

Open Source software

created in the Open Source Community FREE to use with SOURCE CODE :D "Open source may be commercial and carry a cost. Open source software is usually free, but you can use and enhance the software" BUT MUST FOLLOW LICENSE AGREEMENTS "GNUs Public License" -some are made available with what is known as a copyleft instead of a copyright PRIVILEGES: 1.you may enhance the software 2.you may distribute the software *****must abide by the COPYRIGHT provided with the software****

Servers are...

dedicated computers within a network whose function is to respond to network requests and provide network service -designed to handle networking, Internet/intranet hosting, and other functions in businesses -common for servers to use Unix or Linux as their operating systems.

OS History

early computers had no OS -users: programmers and engineers. -ran by punch cards for input, with the output being saved to tape Development of language translators created need for OS -1: compile (or assemble) the program from its original language into machine language...first compile (or assemble) the program from its original language into machine language -2:the source code would have to be input, again from tape or punch card 3:program would execute, loading the source code, translating the source code, and saving the resulting executable code onto magnetic tape 4:executable program would be input from tape, with data being input again from card or tape 5:program would be executed, and the output would be sent to magnetic tape to be printed later --------WITHOUT OS, WE WOULD DO THIS FOR EVERY INPUT/OUTPUT TASK----------- Improvement of hardware led to OSs improvement by: 1. improved speed led to programs requiring less time to execute 2.improved reliability of computers OSs grew more complex with the development of multi programming and time-sharing (multitasking)

File Server

like a computer with a large hard disk that stores files that any or many users of the network can access -supports file sharing, easy backup of user files, encryption of data storage and allows for remote access to files -can store data files or software and run them over the network -USED TO BE POPULAR in computer networks bc hard disk storage was expensive There are many different file servers available with NFS (the Network File System) being the most popular in the Unix/Linux world.

OS for Workstations, Mobile devices and Servers..........

mobile devices and servers also need operating systems in order to allow users to interact with their hardware and software -WORKSTATIONS: multiple operating systems for workstations as discussed previously: Windows 7/8/10, Linux, and Mac OS X -MOBIL: android, windows, iOS -SERVERS: Windows Server (series of OSs than desktop OS) designed to handle networking, Internet/intranet hosting, and other functions in businesses .........common for servers to use Unix or Linux as their operating systems. WINDOWS: provides OS software for various types of computers. For example, Windows Server 8 for servers, Windows 8 for workstations, and Windows Phone 8 for smaller mobile devices such as phones UNIX: does same as windows Unix server for servers, Linux application for workstations, Android: which is a Linux-based mobile OS -Apple's Mac OS X uses Unix as a base for its OS

octal numbering system

octal numbering system, every value is represented with some combination of 8 digits (0-7) - base 8. use this to translate binary system

Creative Commons (CC) license

one of several public copyright licenses that enable the free distribution of an otherwise copyrighted work -CC license is used when an author wants to give people the right to share, use, and build upon a work that he/she has created OTHERS CAN EDIT MY WORK AND DISTRIBUTE IT

PATENTS

protect the creation of inventive concepts as well as the tangible work product (not just the tangible work, as copyrights do) To get patent, the applicant must be able to show that the idea is: -original -useful -not obvious to someone of "ordinary skill" in the field PRIVILEGES: 1. prevent others from making, selling, or using the patented invention for 20 years from the patent application filing date Patent law states that laws of nature, natural phenomena, and abstract ideas cannot be patented NEGATIVES: messy for software, much debate 1. math cannot be patented SO, many believe that software should treated similarly.

Email Server

provides e-mail service job: accept e-mail requests from clients, send messages out to other e-mail servers, receive e-mails from other servers, and alert the user that e-mail has arrived -Linux and Unix operating systems have a built-in e-mail service, sendmail -Windows: variety of e-mail servers available including Eudora, CleanMail, and Microsoft Windows Server Unlike FTP and Web servers, which have a limited number of protocols to handle (primarily FTP, FTPS, HTTP, and HTTPS), there are more e-mail protocols that servers have to handle: IMAP, POP3, SMTP, HTTP, MAPI, and MIME.

Proprietary or commercial software

purchased from a vendor usually made by: -a company that commercially markets software (usually referred to as a software house) -a company that produces its own in-house software -a consultant (or consultant company) hired to produce software "End User License Agreement" or a "Software License Agreement." YOUR PRIVILEGES; 1. you receive the software itself, in EXECUTABLE form -software is installed via an installation program OR If you have purchased it from a consultant, they can do the installation themselves 2.you are provided a LICENSE to use the software -usually this merely gives you the right to use the software, but it is not yours to own 3. sometimes the purchase gives you access to helpful RESOURCES -this can be: user manuals, technical support, online help, or some combination

resident monitor

resident monitor was created to handle these operations based on a few commands rather than dozens or hundreds of program instructions.

Web Server

responds to HTTP requests, usually from web browsers -HTTP: hypertext transfer protocol , usually done for HTML documents (or variants of html) -HTTP and FTP are similar bc a file is TRANSFERRED using the web service

Software Architecture (MVC)

separates the user interface into different components: the model, the view, and the controller -development technique used in the implementation of user interfaces. -application where the various design logic (input, business, and interface) are logically separated ***user interacts with the controller*** ADVANTAGES: useful in separating the programming logic between input logic, business logic, and interface logic. model: develop query which wound present the information in a view (report) -changes and updates are made to the data based on new data ***** -can be actual object that is an actual implementation of the application (think of hierarchy, top down) -in the model layer that the business logic is designed.**** controller: manipulate app part of an application that interacts with the user (via the view) and passes along the user requests to the model -comms btwn model and view*** -results from the model will determine the type of view the controller uses in the interface presented to user -input logic is designed here**** view: when you LOOK at the app/represents the user interface - used to capture user input data*** -view is used to capture input from the user to be passed on via the controller to the model -information returned by the model is then presented to the user via the view ***** interface logic is designed here***** DIFFERENCE : N-tier development model is where each tier is a separate application

SHELL

shell is an interface for the user (often personalized for that given user) -shell provides access to the kernel ex:GUI shell will translate mouse motions into calls to kernel routines (e.g., open a file, start a program, move a file) ex:Desktop elements include shortcut icons, the theme of the windows, menus and background, the appearance of toolbars and programs on the start menu, and desktop gadgets. ORDER: hardware, kernel, shell, software, user

Software Architecture (N-tier)

shield the user from the underlying logic of the system as well as the underlying data structures. ex: e-commerce website (AMAZON) customer does not need to understand what relations from the database the product information is coming from nor should they need to run a query to determine if the products they wish to purchase are available in inventory Presentation : Looks -easy to use interface logic tier: brains/logic processing -logic tier sits between the user interface and the data -looks at past searches and throws graphics of related -middle man btwn what you see and the database behind the scenes (grabs the relevant and compiled data) pulls it together and presents it ex: logic tier is where a query will be run to determine the quantity of items in an order, the price, the available shipping date, etc. resides in the server data: The data tier stores, retrieves, and updates data from tables. -By separating the data from the application logic in the logic-tier the data is made INDEPENDENT of the application ADVANTAGES; -data can change without the need to change the application and vice versa -scale more easily -having data independent removes the need for the user to interact directly with the data, shielding them from the complexities of queries and other application functions resides in organizations server** usually on a separate database server***********************

public domain software

software that has been moved into the public domain -FREE (no money needed) PRIVILEGES: 1. can use it however you like -no one has rights to it or claiming any rights to it 2. available as executables

local application

software that is stored on an individual computer -local application will limit those who could access the application to the owner of the local computer

SERVER

software that works with hardware to provide a network service -includes: print service, ftp server, webserver, email server, database server, and file software

Scripting languages

term script is sometimes used to refer to a small program (i.e., one that contains relatively few lines of code) -scripts are typically fairly short and the instructions are relatively simple (as compared to applications or systems software) USED MORE FOR AUTOMATION THAN FOR SOFTWARE DEV ********INTERPRETED ******** This coding for a specific environment EX: JavaScript is designed to be used inside a web browser environment LIST: ASP JSP PHP Perl Tcl Python

characters

two common forms of character representation, ASCII (American Standard Code for Information Interchange) and Unicode -two common forms of character representation, ASCII (American Standard Code for Information Interchange) and Unicode The way ASCII works is that in place of the character, we have the binary sequence ex: 'a' is stored as the decimal value 97

TYPES OF LANGUAGE TRANSLATORS

two ways in which a high-level language must be converted into machine code 1. Compiling: translates the entire program. This creates an executable program which can be run at a later time. DISADVANTAGE: Not portable -The program itself is portable in that it can be compiled differently for different computers ex: not portable because the entire program was translated into a certain machine code specific to a certain type of computer, like a Mac or a PC. 2. interpreting: Takes the most recently entered instruction, translates it into machine language, and executes it. -interpreter takes the most recently entered instruction, translates it into machine language, and executes it *** scripting languages are interpreted MOSTLY DISADVANTAGE: every instruction is translated first and then executed... do this every time program is ran SLOOWWW GOOD FOR TESTING ; DONE IN PIECEMEAL The result of these are languages that are COMPILED OR INTERPRETED

relationships

user Applications [OS Utilities Services Shells OS Kernel Software Device Drivers] (OS components) OM BIOS Drivers Hardware

Freeware Software

usually software that has become OBSOLETE because a newer software has replaced it OR is software that the original producer (whether an individual or a company) no longer wishes to maintain and provide support for PRIVILEGES: 1. You are bound by some agreements when you install it, but otherwise you are free to use it as if you have purchased it.