SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

C H A P T E R

2
Irwin/McGraw-Hill

INFORMATION
...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

Chapter Two Information System Building Blocks
•...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

Chapter Map

Irwin/McGraw-Hill

Copyright © 2000...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

Data and Information

Data are raw facts about t...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

Information Systems & Technology

An information...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

Front- and Back-Office Information Systems
• Fro...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

A Federation of Information Systems

Irwin/McGra...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

Classes of Information Systems

•
•
•
•
•

Trans...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

Transaction Processing

Transaction processing s...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

Management Information Systems

A management inf...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

Decision Support Systems

A decision support sys...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

Expert Systems

An expert system is a programmed...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

Office Automation Systems

Office automation (OA...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

Information Systems Applications

Irwin/McGraw-H...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

Information Systems Architecture

Information sy...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

Perspectives or Stakeholders
• System owners pay...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

Focuses for Information Systems

• Data—the raw ...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

Information System Building Blocks

Irwin/McGraw...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

The DATA Focus

Irwin/McGraw-Hill

Copyright © 2...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

The DATA Focus

• System owners’ perspective
– B...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

The PROCESS Focus

Irwin/McGraw-Hill

Copyright ...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

The PROCESS Focus

• System owners’ perspective
...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

The PROCESS Focus (continued)

• System users’ p...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

The PROCESS Focus (continued)

• System designer...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

The INTERFACE Focus

Irwin/McGraw-Hill

Copyrigh...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

The INTERFACE Focus

• System owners’ perspectiv...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

Information System Building Blocks

Irwin/McGraw...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

The Role of the Network in IS

Irwin/McGraw-Hill...
SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition

Whitten Bentley Dittman

A COMMUNICATIONS Focus in IS

Irwin/McGraw-Hill
...
Upcoming SlideShare
Loading in …5
×

Asi Chap002

292
-1

Published on

Analisis Sistem Informasi

Published in: Education, Business, Technology
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total Views
292
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
17
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide
  • <number>
    Chapter 2 - Information System Building Blocks
    This repository of slides is intended to support the named chapter. The slide repository should be used as follows:
    Copy the file to a unique name for your course and unit.
    Edit the file by deleting those slides you don’t want to cover, editing other slides as appropriate to your course, and adding slides as desired.
    Print the slides to produce transparency masters or print directly to film or present the slides using a computer image projector.
    Each slide includes instructor notes. To view those notes in PowerPoint, click left on the View Menu; then click left on Notes View sub-menu. You may need to scroll down to see the instructor notes.
    The instructor notes are also available in hard copy as the Instructor Guide to Accompany Systems Analysis and Design Methods, 5/ed. Contact your Irwin/McGraw-Hill sales representative if you need a hard copy.
  • No additional notes
  • Teaching Notes
    This is the capstone figure for the chapter—the complete information systems building blocks framework.
    Teaching Tips
    Emphasize that ALL building blocks are relevant to ALL information systems that the student will encounter or develop during the course of their career.
    Emphasize that the building blocks must be synchronized both horizontally and vertically when building information systems.
    Vertical synchronization ensures that each block represents fully the perspectives of the other blocks in the same column. For example, a database schema must implement the intended data requirements.
    Horizontal synchronization ensures that each block in a given row is consistent and complete with respect to the other blocks in that same row. For example, each table in a database schema requires application software and specifications to maintain the data stored in those tables.
  • No additional notes
  • Conversion Notes
    In previous editions, we tried to distinguish between “information systems” and “computer applications” (the latter being a subset of the former). This created more confusion with students than it was worth.
    Some books use the term “computer technology.” We prefer the more contemporary term, “information technology” as a superset of computer technology.
  • Conversion Notes
    This classification scheme comes from popular usage in the trade literature.
    Teaching Tips
    This terminology is not to be confused with office automation. In fact, office automation systems can be either front-office or back-office, just as with other types of information system applications.
  • Teaching Tips
    This slide visually illustrates front- and back-office applications and highlights the following:
    Many organizations purchase their back-office systems in the form of enterprise resource planning (ERP) products such as SAP, PeopleSoft, and Oracle.
    The ERP industry is trying to expand into the front-office applications.
    It might be noted that electronic commerce and business extensions are being added to both front- and back-office applications in order to streamline interfaces to both customers and suppliers.
    E-commerce is being driven by the Internet (and private extranets).
    E-business is being enabled by intranets.
  • No additional notes
  • No additional notes
  • Conversion Notes
    In some previous editions and other textbooks, MIS is referred to as “management reporting.”
  • Conversion Notes
    Some books treat DSS and EIS as distinct; however, if definitions are closely examined, the differences are subtle – they only differ in audience. Both DSS and EIS tend to support the same decision-oriented activities and basically work the same.
    Data warehouse concepts are also taught in most database textbooks and courses. The design of a data warehouse differs significantly from traditional, operational databases.
  • No additional notes
  • No additional notes
  • Teaching Tips
    It may be useful to walk through this diagram in class. The textbook coverage included numbered annotations that highlight portions of this diagram.
    Remind students that any given information system may include many instances of each of these IS application processes and databases.
  • No additional notes
  • Conversion Notes
    For this edition, we added systems analysts and IT vendors and consultants.
    Each of these classes of stakeholders is described in greater detail in Chapter 1.
    Note that we use a consistent color for these stakeholders (throughout the chapter and textbook).
    Teaching Tips
    It is very important for students to understand that these are “roles,” not “job titles.”
    Any given individual can play more than one role.
    Any role is shared by many individuals.
  • Conversion Notes
    We deleted the “geography” focus (column) from this edition. It still exists; however, the technology architecture and network for an organization is typically developed separate from the information system, and typically supports many information systems and communications needs. By eliminating this column in the fifth edition, we have simplified the framework for the students. The book still presumes that the network is a critical component for all contemporary information systems.
  • Teaching Notes
    This slide serves to establish the focus for the chapter. The highlighted cells are the information system building blocks that are described in detail as this chapter unfolds.
  • Teaching Notes
    This slide visually illustrates the chapter’s discussion of the DATA focus as seen by different stakeholders.
    Teaching Tips
    If your students have taken a database course, it can be useful to summarize that experience within the context of the DATA column.
  • Teaching Notes
    This slide places definitions and key terms relevant to the DATA focus into the context of stakeholders.
  • Teaching Notes
    This slide visually illustrates the chapter’s discussion of the PROCESS focus as seen by the different stakeholders.
    Teaching Tips
    Most students have some programming experience. Accordingly, it can be useful to summarize that experience within the context of the PROCESS column. Consider summarizing that experience by working bottom-to-top in the column to reinforce their perspective of the “application programs” they wrote.
    The programming instructor typically played the roles of system owners, users, and analysts when they wrote the programming assignments.
    The student typically played the roles of designer (e.g., flowcharts) and builder (e.g, logic).
  • Teaching Notes
    This slide places definitions and key terms relevant to the PROCESS focus into the context of stakeholders.
  • Teaching Notes
    This slide places definitions and key terms relevant to the PROCESS focus into the context of stakeholders.
  • Teaching Notes
    This slide places definitions and key terms relevant to the PROCESS focus into the context of stakeholders.
  • Teaching Notes
    This slide visually illustrates the chapter’s discussion of the INTERFACE focus as seen by the different stakeholders.
    Teaching Tips
    Many students have written programs for graphical user interfaces using languages such as Access, Visual Basic and HTML. Accordingly, it can be useful to summarize that experience within the context of the INTERFACE column.
    While it is conceptually and practically useful to separate INTERFACE and PROCESS, it should be noted that many of today’s contemporary application development environments (ADEs) such as Visual Basic effectively integrate the technology used to construct both the user interface and the application logic. Some students find this confusing.
    Interestingly, the emphasis on Web-based applications is truly separating the concerns. For example, the interface elements of a Web are written in HTML while the application logic is written in C++ or Java.
  • Teaching Notes
    This slide places definitions and key terms relevant to the INTERFACE focus into the context of stakeholders.
  • Teaching Notes
    This is the capstone figure for the chapter—the complete information systems building blocks framework.
    Teaching Tips
    Emphasize that ALL building blocks are relevant to ALL information systems that the student will encounter or develop during the course of their career.
    Emphasize that the building blocks must be synchronized both horizontally and vertically when building information systems.
    Vertical synchronization ensures that each block represents fully the perspectives of the other blocks in the same column. For example, a database schema must implement the intended data requirements.
    Horizontal synchronization ensures that each block in a given row is consistent and complete with respect to the other blocks in that same row. For example, each table in a database schema requires application software and specifications to maintain the data stored in those tables.
  • Conversion Notes
    This slide illustrates the classic model of separating and partitioning the layers of an information system application across a network.
    This is called a distributed computing architecture and it can be implemented using either client/server or Internet/intranet technology, or a combination of both.
  • Conversion Notes
    While we deleted the GEOGRAPHY column that was included in our framework in the fourth edition, we did not want to ignore it. Today’s information systems are built on top of constantly evolving networks.
    This slide was adapted from the margin art to illustrate that the framework works equally well for network analysis and design.
    We acknowledge that a more complicated and well-accepted framework exists in the form of the OSI model. That is yet another reason we chosen to deemphasize this column in our fifth edition.
  • Asi Chap002

    1. 1. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman C H A P T E R 2 Irwin/McGraw-Hill INFORMATION SYSTEM BUILDING BLOCKS Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    2. 2. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman Chapter Two Information System Building Blocks • • • • • • • • • • • • What are information systems, and who are the stakeholders in the information systems game? Describe the difference between data and information. Define the product called an information system, and describe the role of information technology in information systems. Differentiate between front- and back-office information systems. Describe five classes of information system applications (transaction processing, management information, decision support, expert, and office automation systems) and how they interoperate. Describe the role of information systems architecture in system development. Name six groups of stakeholders in information system development. Name three focuses for information systems. Describe four perspectives of the DATA focus for an information system. Describe four perspectives of the PROCESS focus for an information system. Describe four perspectives of the INTERFACE focus for an information system. Describe the role of a computer network as it relates to DATA, PROCESSES, and INTERFACES. Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    3. 3. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman Chapter Map Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    4. 4. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman Data and Information Data are raw facts about the organization and its business transactions. Most data items have little meaning and use by themselves. Information is data that has been refined and organized by processing and purposeful intelligence. The latter, purposeful intelligence, is crucial to the definition—People provide the purpose and the intelligence that produces true information. Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    5. 5. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman Information Systems & Technology An information system (IS) is an arrangement of people, data, processes, communications, and information technology that interact to support and improve day-to-day operations in a business as well as support the problem-solving and decision making needs of management and users. Information technology is a contemporary term that describes the combination of computer technology (hardware and software) with telecommunications technology (data, image, and voice networks). Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    6. 6. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman Front- and Back-Office Information Systems • Front-office information systems support business functions that reach out to customers (or constituents). – Marketing – Sales – Customer management • Back-office information systems support internal business operations and interact with suppliers (of materials, equipment, supplies, and services). – – – – Human resources Financial management Manufacturing Inventory control Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    7. 7. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman A Federation of Information Systems Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    8. 8. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman Classes of Information Systems • • • • • Transaction processing systems Management information systems Decision support systems Expert systems Office automation systems Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    9. 9. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman Transaction Processing Transaction processing systems are information system applications that capture and process data about business transactions. – Includes data maintenance, which provides for custodial updates to stored data. – Business process redesign (BPR) is the study, analysis, and redesign of fundamental business (transaction) processes to reduce costs and/or improve value added to the business. Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    10. 10. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman Management Information Systems A management information system (MIS) is an information system application that provides for management-oriented reporting. These reports are usually generated on a predetermined schedule and appear in a prearranged format. Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    11. 11. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman Decision Support Systems A decision support system (DSS) is an information system application that provides its users with decisionoriented information whenever a decision-making situation arises. When applied to executive managers, these systems are sometimes called executive information systems (EIS). – A data warehouse is a read-only, informational database that is populated with detailed, summary, and exception data and information generated by other transaction and management information systems. The data warehouse can then be accessed by endusers and managers with DSS tools that generate a virtually limitless variety of information in support of unstructured decisions. Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    12. 12. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman Expert Systems An expert system is a programmed decision-making information system that captures and reproduces the knowledge and expertise of an expert problem solver or decision maker and then simulates the “thinking” or “actions” of that expert. – Expert systems are implemented with artificial intelligence technology that captures, stores, and provides access to the reasoning of the experts. Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    13. 13. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman Office Automation Systems Office automation (OA) systems support the wide range of business office activities that provide for improved work flow and communications between workers, regardless of whether or not those workers are located in the same office. – Personal information systems are those designed to meet the needs of a single user. They are designed to boost an individual’s productivity. – Work group information systems are those designed to meet the needs of a work group. They are designed to boost the group’s productivity. Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    14. 14. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman Information Systems Applications Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    15. 15. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman Information Systems Architecture Information systems architecture provides a unifying framework into which various people with different perspectives can organize and view the fundamental building blocks of information systems. Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    16. 16. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman Perspectives or Stakeholders • System owners pay for the system to be built and maintained. • System users use the system to perform or support the work to be completed. • System designers design the system to meet the users’ requirements. • System builders construct, test, and deliver the system into operation. • Systems analysts facilitate the development of information systems and computer applications by bridging the communications gap that exists between nontechnical system owners and users and technical system designers and builders. • IT vendors and consultants sell hardware, software, and services to businesses for incorporation into their information systems. Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    17. 17. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman Focuses for Information Systems • Data—the raw material used to create useful information. • Processes—the activities (including management) that carry out the mission of the business. • Interfaces—how the system interfaces with its users and other information systems. Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    18. 18. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman Information System Building Blocks Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    19. 19. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman The DATA Focus Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    20. 20. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman The DATA Focus • System owners’ perspective – Business knowledge is the insight that is gained from timely, accurate, and relevant information. (Recall that information is a product of raw data.) • System users’ perspective – Data requirements are a representation of users’ data in terms of entities, attributes, relationships, and rules. Data requirements should be expressed in a format that is independent of the technology that can or will be used to store the data. • System designers’ perspective – Database schema • System builders’ perspective – Database management system Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    21. 21. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman The PROCESS Focus Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    22. 22. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman The PROCESS Focus • System owners’ perspective – Business functions are ongoing activities that support the business. Functions can be decomposed into other subfunctions and eventually into processes that do specific tasks. – A cross-functional information system supports relevant business processes from several business functions without regard to traditional organizational boundaries such as divisions, departments, centers, and offices. Continued ... Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    23. 23. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman The PROCESS Focus (continued) • System users’ perspectives – Business processes are activities that respond to business events. Business processes are the “work” performed by the system. – Process requirements are a representation of the users’ business processes in terms of activities, data flows, or work flow. – A policy is a set of rules that govern a business process. – A procedure is a step-by-step set of instructions and logic for accomplishing a business process. Continued ... Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    24. 24. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman The PROCESS Focus (continued) • System designers’ perspectives – An application schema is a model that communicates how selected business processes are, or will be, implemented using the software and hardware. – Software specifications represent the technical design of business processes to be automated or supported by computer programs to be written by system builders. • System builders’ perspectives – Application programs are language-based, machinereadable representations of what a software process is supposed to do, or how a software process is supposed to accomplish its task. – Prototyping is a technique for quickly building a functioning, but incomplete model of the information system using rapid application development tools. Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    25. 25. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman The INTERFACE Focus Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    26. 26. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman The INTERFACE Focus • System owners’ perspective • System users’ perspectives – Interface requirements are a representation of the users’ inputs and outputs. • System designers’ perspective – User dialogues describe how the user moves from window-to-window, interacting with the application programs to perform useful work. • System builders’ perspective – Middleware is a layer of utility software that sits in between application software and systems software to transparently integrate differing technologies so that they can interoperate. Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    27. 27. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman Information System Building Blocks Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    28. 28. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman The Role of the Network in IS Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    29. 29. SYSTEMS ANALYSIS AND DESIGN METHODS 5th Edition Whitten Bentley Dittman A COMMUNICATIONS Focus in IS Irwin/McGraw-Hill Copyright © 2000 The McGraw-Hill Companies. All Rights reserved
    1. A particular slide catching your eye?

      Clipping is a handy way to collect important slides you want to go back to later.

    ×