The requirements analysis is important because it will play a major role in determining the design of specific software and hardware systems．
Often，systems analysts in medium and large-scale organizations must use an existing system on which they base their requirements analysis．In this case，gaining an understanding of the existing system can be viewed as a background study that is a preliminary phase to the definition phase．A systems analyst would analyze an existing system and produce a written document that would identify the following：
• The needs of the people who use the system；
• The existing inputs，outputs，and processing；
• The flow of information through the system．
Once a good understanding of the existing system has been acquired，it serves as a basis for a detailed functional specification in which problems and opportunities to improve effectiveness can be identified and communicated to others[1]．The analyst should always examine the existing system to see if needs can be met without a new system．
As information is collected about the current system，it should be organized so that every possible solution and its feasibility can be examined．The systems analyst works with users to analyze the alternatives．In this case，the goal of the background study is to：
• Identify and prioritize system-related problems and costs；
• Identify opportunities to improve systems performance；
• Produce a functional specification．
On the other hand，in many cases a systern must be designed to fill a need that did not exist beforehand．New computer systerns are often technology-driven．That is，as a technology becomes feasible to implement，it presents new business opportunities．For example，the automated teller machines（ATMs）presented the banking industry with a new opportunity．In that case，the process did not start with a request from a user，but as an opportunity created by new computer software and hardware．
The requirements analysis is one of the most important tasks to undertake，because it answers such questions as：
• What is the user’s problem？
• Will a computer help？
• What is the system required to do？
• What are some preliminary approaches to the problem？
NOTES
[1] “… a businessperson，such as the manager of a department，should consider”是省略關(guān)系代詞“that”的限定性定語(yǔ)從句，修飾主語(yǔ)“questions”，其中“such as…”是插入語(yǔ)，說(shuō)明“businessperson”。
[2] “to handle”引出的不定式短語(yǔ)，作定語(yǔ)修飾“a word processing application”；其后which引導(dǎo)的非限制性定語(yǔ)從句修飾“correspondence”。
[3] 句中有3個(gè)“that”，前兩個(gè)that，即“that…and that…”引導(dǎo)兩個(gè)并列的賓語(yǔ)從句；最后一個(gè)“that”引導(dǎo)定語(yǔ)從句，修飾“word processing package”。
[4] “in which”到句末為引導(dǎo)詞是介詞賓語(yǔ)的定語(yǔ)從句；其中“to improve effectiveness”為不定式短語(yǔ)，作定語(yǔ)修飾“problems and opportunities”。
Often，systems analysts in medium and large-scale organizations must use an existing system on which they base their requirements analysis．In this case，gaining an understanding of the existing system can be viewed as a background study that is a preliminary phase to the definition phase．A systems analyst would analyze an existing system and produce a written document that would identify the following：
• The needs of the people who use the system；
• The existing inputs，outputs，and processing；
• The flow of information through the system．
Once a good understanding of the existing system has been acquired，it serves as a basis for a detailed functional specification in which problems and opportunities to improve effectiveness can be identified and communicated to others[1]．The analyst should always examine the existing system to see if needs can be met without a new system．
As information is collected about the current system，it should be organized so that every possible solution and its feasibility can be examined．The systems analyst works with users to analyze the alternatives．In this case，the goal of the background study is to：
• Identify and prioritize system-related problems and costs；
• Identify opportunities to improve systems performance；
• Produce a functional specification．
On the other hand，in many cases a systern must be designed to fill a need that did not exist beforehand．New computer systerns are often technology-driven．That is，as a technology becomes feasible to implement，it presents new business opportunities．For example，the automated teller machines（ATMs）presented the banking industry with a new opportunity．In that case，the process did not start with a request from a user，but as an opportunity created by new computer software and hardware．
The requirements analysis is one of the most important tasks to undertake，because it answers such questions as：
• What is the user’s problem？
• Will a computer help？
• What is the system required to do？
• What are some preliminary approaches to the problem？
NOTES
[1] “… a businessperson，such as the manager of a department，should consider”是省略關(guān)系代詞“that”的限定性定語(yǔ)從句，修飾主語(yǔ)“questions”，其中“such as…”是插入語(yǔ)，說(shuō)明“businessperson”。
[2] “to handle”引出的不定式短語(yǔ)，作定語(yǔ)修飾“a word processing application”；其后which引導(dǎo)的非限制性定語(yǔ)從句修飾“correspondence”。
[3] 句中有3個(gè)“that”，前兩個(gè)that，即“that…and that…”引導(dǎo)兩個(gè)并列的賓語(yǔ)從句；最后一個(gè)“that”引導(dǎo)定語(yǔ)從句，修飾“word processing package”。
[4] “in which”到句末為引導(dǎo)詞是介詞賓語(yǔ)的定語(yǔ)從句；其中“to improve effectiveness”為不定式短語(yǔ)，作定語(yǔ)修飾“problems and opportunities”。