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+# zPages
+> Last updated 6/26/20
+
+# Table of Contents
+- [Summary](#summary)
+  - [TraceZ](#tracez)
+  - [RPCz](#rpcz)
+- [Usage](#usage)
+- [Links of Interest](#links-of-interest)
+
+## Summary
+zPages allow easy viewing of tracing information. When included for a process, zPages will display basic information about that process on a webpage. There are currently two types of zPages: TraceZ and RPCz.
+
+Including a zPage within a page is useful for developers because it's quicker to get running than adding extra code and installing external exporters like Jaeger and Zipkin. zPages tend to be more lightweight than these external exporters, but are also helpful for debugging latency issues and deadlocks.
+
+The idea of "zPages" originates from one of OpenTelemetry's predecessors, [OpenCensus](https://opencensus.io/). You can read more about it [here](https://opencensus.io/zpages). OpenCensus has different zPage implementations in [Java](https://opencensus.io/zpages/java/), [Go](https://opencensus.io/zpages/go/), and [Node](https://opencensus.io/zpages/node/) and there has been similar internal solutions developed at companies like Uber, but *this is the first major open-source implementation of zPages in C++*. Within OpenTelemetry, zPages are also being developed in [Java](https://github.com/open-telemetry/opentelemetry-java).
+
+#### How It Works
+On a high level, zPages work by reading a process' spans using a SpanProcessor, which exports spans to the appropriate DataAggregator that a HttpServer uses.
+
+> TODO: Add picture examples for span overview and individual span view
+
+### TraceZ
+TraceZ is a type of zPage that shows information on tracing spans, and allows users to look closer at specific and individual spans. Details a user would view include span id, name, status, and timestamps. The individual components of TraceZ are as follows:
+
+- TracezSpanProcessor (TSP)
+  - Contact point for TraceZ to connect with a process, which collects tracing information and provides an interface for TDA.
+- TracezDataAggregator (TDA)
+  - Intermediary between the TSP and THS, which also performs various functions and calculations to send the correct tracing information to the THS.
+- TracezHttpServer (THS)
+  - User-facing web page generator, which creates HTML pages using TDA that display 1) overall information on all of the process's spans and 2) more detailed information on specific spans when clicked.
+
+### RPCz
+RPCz is a type of zPage that provides details on instrumented sent and received RPC messages. Although there is currently no ongoing development of RPCz for OpenTelemetry, OpenCensus zPages have implementations of RPCz (linked above).
+
+# Usage
+
+> TODO: Add instructions to add zPages
+
+## Links of Interest
+- [TracezSpanProcessor Design Doc](https://docs.google.com/document/d/1kO4iZARYyr-EGBlY2VNM3ELU3iw6ZrC58Omup_YT-fU/edit#) (pending review)
+- [TracezDataAggregator Design Doc](https://docs.google.com/document/d/1ziKFgvhXFfRXZjOlAHQRR-TzcNcTXzg1p2I9oPCEIoU/edit?ts=5ef0d177#heading=h.5irk4csrpu0y) (pending review)
+- [TracezHttpServer Design Doc](https://docs.google.com/document/d/1U1V8QZ5LtGl4Mich-aJ6KZGLHrMIE8pWyspmzvnIefI/edit#) (draft)
+- [Contribution Guidelines](https://github.com/open-telemetry/opentelemetry-cpp/blob/master/CONTRIBUTING.md)
+
+