[Mapzen Search](https://mapzen.com/projects/search) is a modern, geographic search service based entirely on open-source tools and powered entirely by open data. You might use this functionality in any app that has a geographic component, including ones that deliver goods, locate hotels or venues, or even provide local weather forecasts.
Through a process known as [geocoding](https://en.wikipedia.org/wiki/Geocoding), Mapzen Search allows you to enter an address or the name of a landmark or business, and then it translates the result in to the geographic coordinates for mapping. Mapzen Search is built on [Pelias](https://github.com/pelias), an open-source geocoding project.
In this walkthrough, you will learn how to make a map with a search box that allows you to enter addresses and place names and locate them on a map. To complete the tutorial, you should have some familiarity with HTML and JavaScript, although all the source code is provided.
The Leaflet JavaScript library, which provides tools for zooming, displaying attributions, and drawing symbols, is a framework you can use to build web and mobile maps. Leaflet is extensible, and developers have built additional tools for Leaflet maps, including the Mapzen Search geocoder plug-in.
To set up your development environment for this walkthrough, you need to download the geocoder plug-in. You do not need to download the Leaflet files because you will be referencing them from a web server.
1. Download the zip file from https://github.com/pelias/pelias-doc/raw/master/geocoding-tutorial.zip.
2. Find the file in your default downloads directory and unzip it. It should unzip to a folder named geocoding-tutorial. (Note that some browsers, such as Safari, may unzip automatically.)
Suggested text editor applications include [Atom - OS X, Windows, Linux](https://atom.io/), [Notepad++ - Windows](https://notepad-plus-plus.org/), [TextWrangler - OS X](http://www.barebones.com/products/textwrangler/), and [Sublime - OS X, Windows, Linux; free trial](http://www.sublimetext.com/). While you can use the apps installed with your operating system, such as Notepad or TextEdit, they do not provide the helpful indentations, code coloring and autocomplete, or text alignment options found in the other editors. For TextEdit, you must go to the Format menu and click Make Plain Text to use the plain-text version of the file. Do not use an app that applies rich formatting, such as Word or Wordpad.
The geocoding-tutorial folder contains two HTML files: `index.html` is the file you will start with and update in the steps, while `index-complete.html` is a finished version to check your work or review if you need to troubleshoot an error.
These form the basic structure of an HTML document. `<!DOCTYPE html>` goes at the top of every HTML page and indicates that it is written for HTML5, and the `<html>` tags tell your browser that the content is HTML. The `<head>` tag contains the title for the page and other metadata about the page, while the `<body>` is where you add the code and the rest of the content on your page. There are many [web tutorials](http://www.w3schools.com/html/default.asp) available to help you experiment with and learn more about building HTML documents and the tags in them.
A cascading style sheet (CSS) is used to style a webpage, including layout and fonts, and JavaScript adds functionality to the page. In your index.html file, you need to list the CSS and JavaScript files required for building a page with Leaflet and the geocoder plug-in.
1. In index.html, at the bottom of the `<head>` section, add references to the Leaflet CSS and JavaScript files. You are linking to these on a website, rather than from a file on your machine.
2. In the `<head>` section, immediately after the lines you added for Leaflet, add references to the geocoder's CSS and JavaScript files. These files are from the zipped file you copied to your machine.
3. Save your edits and refresh the browser. The webpage should still appear empty because you have not added any code to interact with these references.
To display a Leaflet map on a page, you need a `<div>` element with an ID value, as well as a size for the box containing the map. If you want to know more about initializing a Leaflet map, see the [Leaflet getting started documentation](http://leafletjs.com/examples/quick-start.html).
1. At the bottom of the `<head>` section, after the references you added in the previous steps, add a `<style>` tag and the following attributes to set the size of the map on your webpage.
`L.xxxxx` is a convention used with the Leaflet API. The `setView([37.804146, -122.275045], 16)` part sets the center of the map, in decimal degrees, and the zoom level. The map is centered at the MaptimeOAK meeting location, with a zoom level that allows you to see the streets and features of the city. Zoom levels are similar to map scales or resolutions, where a smaller value shows a larger area in less detail, and a larger zoom level value depicts smaller area in great detail.
4. Within the same `<script>` tag, start a new line and set the data source for the map. This line adds the default OpenStreetMap tiles and an attribution.
So far, you have referenced the necessary files, initialized Leaflet with a map container on the page, and added data to the map. Now, you are ready to add the Search box from the Mapzen Search plug-in.
The `search-VzKH_PI` text is the Mapzen Search [API key](https://en.wikipedia.org/wiki/Application_programming_interface_key). Because the search service is shared among many users, an API key is a way to make sure that the performance is acceptable for everyone. The key you are provided at MaptimeOAK will expire, so if you want to use Mapzen Search after this event, you need to obtain your own API key from https://mapzen.com/developers and replace it here.
2. In the results list, find the entry for `555 12th Street, Oakland, CA` and click it to zoom and add a point to the map at that location. (The point is only on your map, and does not update OpenStreetMap.)
Mapzen Search uses a [variety of open data sources](https://mapzen.com/documentation/search/data-sources/), including OpenStreetMap. If you unable to find a location, it could be a software issue, or also an indicator that the place is missing or incorrect in the source dataset. Part of the power of open data is that anyone can modify the source data and improve the quality for everyone.
However, because the geocoder is still under development and considered experimental, if you are getting unexpected search results, please add an issue to the [Pelias GitHub repository](https://github.com/pelias/pelias/issues). The developers can investigate and determine if the problem is caused by software or data, and work to fix it either way.
