1. 关键活动和关键路径
Critical Activity. Any schedule activity on a critical path in a project schedule. Most commonly determined by using the critical path method. Although some activities are “critical,” in the dictionary sense, without being on the critical path, this meaning is seldom used in the project context.(PMBOK2004)
关键活动就是位于关键路径上的活动。
Critical Path [Output/Input]. Generally, but not always, the sequence of schedule activities that determines the duration of the project. Generally, it is the longest path through the project. However, a critical path can end, as an example, on a schedule milestone that is in the middle of the project schedule and that has a finish-no-later-than imposed date schedule constraint. See also critical path method.(PMBOK2004)

2. 自由浮动时间和总浮动时间
Free Float (FF). The amount of time that a schedule activity can be delayed without delaying the early start of any immediately following schedule activities. See also total float.(PMBOK2004)

Float. The amount of time that an activity may be delayed from its early start without delaying the project finish date. Float is a mathematical calculation, and can change as the project progresses and changes are made to the project plan. Also called slack, total float, and path float. See also free float.

Float. Also called slack. See total float and see also free float.(PMBOK2004)
Total Float (TF). The total amount of time that a schedule activity may be delayed from its early start date without delaying the project finish date, or violating a schedule constraint. Calculated using the critical path method technique and determining the difference between the early finish dates and late finish dates. See also free float.(PMBOK2004)
自由浮动时间是指一个活动不影响其紧后活动最早开始时间情况下的机动时间，而总浮动时间是指一个活动不影响项目完成时间或者进度时间限制情况下，所具有的机动时间。

3. 路径
Path. A set of sequentially connected activities in a project network diagram.
Network Path. Any continuous series of connected activities in a project network diagram.

Network Path. Any continuous series of schedule activities connected with logical relationships in a project schedule network diagram.(PMBOK2004)
路径指的是具有逻辑关系的一系列活动，不一定从头到尾，可以是项目中进度中的一段。

4. work,task,activity,milestone的区别
Work. Sustained physical or mental effort, exertion, or exercise of skill to overcome obstacles and achieve an objective. (PMBOK2004)
Work是一个抽象的统称，在OK中没有特指。
Work Package. A deliverable at the lowest level of the work breakdown structure, when that deliverable may be assigned to another project manager to plan and execute. This may be accomplished through the use of a subproject where the work package may be further decomposed into activities. 工作包是WBS分解的最低层次，可以进一步分解为活动。

Task. A term for work whose meaning and placement within a structured plan for project work varies by the application area, industry, and brand of project management software.(PMBOK2004)
Task. A generic term for work that is not included in the work breakdown structure, but potentially could be a further decomposition of work by the individuals responsible for that work. Also, lowest level of effort on a project.(PMBOK2000)
任务：在WBS中没有包括的工作（我认为没有包括是指没有体现出来），但是可能被工作负责人进一步分解，是项目投入的最低级别。

Schedule Activity. A discrete scheduled component of work performed during the course of a project. A schedule activity normally has an estimated duration, an estimated cost, and estimated resource requirements. Schedule activities are connected to other schedule activities or schedule milestones with logical relationships, and are decomposed from work packages.(PMBOK2004)活动需要历时，消耗成本和资源。活动来自对工作包的分解。

Event. Something that happens, an occurrence, an outcome. Schedule Milestone. A significant event in the project schedule, such as an event restraining future work or marking the completion of a major deliverable. A schedule milestone has zero duration. Sometimes called a milestone activity. (PMBOK2004)

Milestone. A significant event in the project, usually completion of a major deliverable.(PMBOK2004)

5. Skill, Technique, Tool
Skill. Ability to use knowledge, a developed aptitude, and/or a capability to effectively and readily execute or perform an activity.
(PMBOK2004)技能是对知识运用的能力，执行或者完成一个活动的能力。
Technique. A defined systematic procedure employed by a human resource to perform an activity to produce a product or result or deliver a service, and that may employ one or more tools.(PMBOK2004)
Technical Performance Measurement [Technique]. A performance measurement technique that compares technical accomplishments during project execution to the project management plan’s schedule of planned technical achievements. It may use key technical parameters of the product produced by the project as a quality metric. The achieved metric values are part of the work performance information.(PMBOK2004)
Tool. Something tangible, such as a template or software program, used in performing an activity to produce a product or result. (PMBOK2004)
工具是客观存在的实体，技术是一种方法和步骤，两者都是客观的。而技能（skill）是指人对技术和工具的应用能力，可以说带有主观性。

PMBOK中9个计划文档
9 plan documents in PMBOK:
Project plan. The project plan is a formal, approved document used to manage project execution. The project schedule lists planned dates for performing activities and meeting milestones identified in the project plan (see Section 6.4.3.1).
The project plan and schedule should be distributed as defined in the communications management plan (e.g., management of the performing organization may require broad coverage with little detail, while a contractor may require complete details on a single subject). In some application areas, the term integrated project plan is used to refer to this document.
A clear distinction should be made between the project plan and the project performance measurement baselines. The project plan is a document or collection of documents that should be expected to change over time as more information becomes available about the project. The performance measurement baselines will usually change only intermittently, and then generally only in response to an approved scope of work or deliverable change.
There are many ways to organize and present the project plan, but it commonly includes all of the following (these items are described in more detail elsewhere):
_ Project charter.
_ A description of the project management approach or strategy (a summary of the individual management plans from the other knowledge areas).
_ Scope statement, which includes the project objectives and the project deliverables.
_ WBS to the level at which control will be exercised, as a baseline scope document.
_ Cost estimates, scheduled start and finish dates (schedule), and responsibility assignments for each deliverable within the WBS to the level at which control will be exercised.
_ Performance measurement baselines for technical scope, schedule, and cost— i.e., the schedule baseline (project schedule) and the cost baseline (timephased project budget).
_ Major milestones and target dates for each.
_ Key or required staff and their expected cost and/or effort.
_ Risk management plan, including: key risks, including constraints and assumptions, and planned responses and contingencies (where appropriate) for each.
_ Subsidiary management plans, namely:
_ Scope management plan (Section 5.2.3.3).
_ Schedule management plan (Section 6.4.3.3).
_ Cost management plan (Section 7.2.3.3).
_ Quality management plan (Section 8.1.3.1).
_ Staffing management plan (Section 9.1.3.2).
_ Communications management plan (Section 10.1.3.1).
_ Risk response plan (Section 11.5.3.1).
_ Procurement management plan (Section 12.1.3.1).
Each of these plans could be included if needed and with detail to the extent required for each specific project.
_ Open issues and pending decisions.
Other project planning outputs should be included in the formal plan, based upon the needs of the individual project. For example, the project plan for a large project will generally include a project organization chart.

Project plan. The project plan is described in Section 4.1.3.1. The subsidiary management plans (scope management plan, risk management plan, procurement management plan, configuration management plan, etc.) and the performance measurement baselines are key inputs to project plan execution.(p46)
Scope management plan. This document describes how project scope will be managed and how scope changes will be integrated into the project. It should also include an assessment of the expected stability of the project scope (i.e., how likely is it to change, how frequently, and by how much). The scope management plan should also include a clear description of how scope changes will be identified and classified. (This is particularly difficult—and therefore absolutely essential—when the product characteristics are still being elaborated.)
A scope management plan may be formal or informal, highly detailed or broadly framed, based on the needs of the project. It is a subsidiary component of the project plan (described in Section 4.1.3.1).
Schedule management plan. A schedule management plan defines how changes to the schedule will be managed.
It may be formal or informal, highly detailed or broadly framed, based on the needs of the project. It is a subsidiary element of the overall project plan (see Section 4.1).
Cost management plan. The cost management plan describes how cost variances will be managed (e.g., different responses to major problems than to minor ones).
A cost management plan may be formal or informal, highly detailed or broadly framed, based on the needs of the project stakeholders. It is a subsidiary element of the project plan (discussed in Section 4.1.3.1).
Quality management plan. The quality management plan should describe how the project management team will implement its quality policy. In ISO 9000 terminology, it should describe the project quality system: “the organizational structure, responsibilities, procedures, processes, and resources needed to implement quality management” (5).
The quality management plan provides input to the overall project plan (described in Section 4.1, Project Plan Development), and must address quality control, quality assurance, and quality improvement for the project.
The quality management plan may be formal or informal, highly detailed, or broadly framed, based on the requirements of the project.
Staffing management plan. The staffing management plan describes when and how human resources will be brought onto and taken off of the project team.
The staffing plan may be formal or informal, highly detailed or broadly framed, based on the needs of the project. It is a subsidiary element of the overall project plan (see Section 4.1, Project Plan Development).
The staffing management plan often includes resource histograms, as illustrated in Figure 9-3.
Particular attention should be paid to how project team members (individuals or groups) will be released when they are no longer needed on the project. Appropriate reassignment procedures may:
_ Reduce costs by reducing or eliminating the tendency to “make work” to fill the time between this assignment and the next.
_ Improve morale by reducing or eliminating uncertainty about future employment opportunities.
Communications management plan. A communications management plan is a document that provides:
_ A collection and filing structure that details what methods will be used to gather and store various types of information. Procedures should also cover collecting and disseminating updates and corrections to previously distributed material.
_ A distribution structure that details to whom information (status reports, data, schedule, technical documentation, etc.) will flow, and what methods (written reports, meetings, etc.) will be used to distribute various types of information. This structure must be compatible with the responsibilities and reporting relationships described by the project organization chart.
_ A description of the information to be distributed, including format, content, level of detail, and conventions/definitions to be used.
_ Production schedules showing when each type of communication will be produced.
_ Methods for accessing information between scheduled communications.
_ A method for updating and refining the communications management plan as the project progresses and develops.
The communications management plan may be formal or informal, highly detailed or broadly framed, based on the needs of the project. It is a subsidiary component of the overall project plan (described in Section 4.1).
Risk management plan. The risk management plan describes how risk identification, qualitative and quantitative analysis, response planning, monitoring, and control will be structured and performed during the project life cycle. The risk management plan does not address responses to individual risks—this is accomplished in the risk response plan, which is discussed in Section 11.5.3.1. The risk
management plan may include the following.
_ Methodology. Defines the approaches, tools, and data sources that may be used to perform risk management on this project. Different types of assessments may be appropriate, depending upon the project stage, amount of information available, and flexibility remaining in risk management.
_ Roles and responsibilities. Defines the lead, support, and risk management team membership for each type of action in the risk management plan. Risk management teams organized outside of the project office may be able to perform more independent, unbiased risk analyses of project than those from the sponsoring project team.
_ Budgeting. Establishes a budget for risk managment for the project.
_ Timing. Defines how often the risk management process will be performed throughout the project life cycle. Results should be developed early enough to affect decisions. The decisions should be revisited periodically during project execution.
_ Scoring and interpretation. The scoring and interpretation methods appropriate for the type and timing of the qualitative and quantitative risk analysis being performed. Methods and scoring must be determined in advance to ensure consistency.
_ Thresholds. The threshold criteria for risks that will be acted upon, by whom, and in what manner. The project owner, customer, or sponsor may have a different risk threshold. The acceptable threshold forms the target against which the project team will measure the effectiveness of the risk response
plan execution.
_ Reporting formats. Describes the content and format of the risk response plan described in Section 11.5.3.1. Defines how the results of the risk management processes will be documented, analyzed, and communicated to the project team, internal and external stakeholders, sponsors, and others.
_ Tracking. Documents how all facets of risk activities will be recorded for the benefit of the current project, future needs, and lessons learned. Documents if and how risk processes will be audited.
Procurement management plan. The procurement management plan should describe how the remaining procurement processes (from solicitation planning through contract closeout) will be managed. For example:
_ What types of contracts will be used?
_ If independent estimates will be needed as evaluation criteria, who will prepare them and when?
_ If the performing organization has a procurement department, what actions can the project management team take on its own?
_ If standardized procurement documents are needed, where can they be found?
_ How will multiple providers be managed?
_ How will procurement be coordinated with other project aspects, such as scheduling and performance reporting?
A procurement management plan may be formal or informal, highly detailed or broadly framed, based on the needs of the project. It is a subsidiary element of the project plan described in Section 4.1, Project Plan Development.