Posting 3: Search engine

Differences and Similarities (MAMA.COM, GOOGLE SCHOOLAR, ERICT DIGEST AND YAHOO.COM).

SIMILARITIES
All of them are freely accessible web engine research. They are provided us to access the information, online searching, publication and many more.
DIFFERENCES.
1. Eric digest
ERIC is a national information system that includes 16 clearinghouses and four support components. ERIC is the world's most widely used education database, with more than 3,000 locations around the world receiving ERIC print or database products. About 900 of these maintain complete microfiche collections and provide search services for clients. It is easy to submit documents to ERIC and authors remain free to submit their work to any journal or publisher. Announcing a document in ERIC can be an effective marketing tool, as people are more apt to want an original document from the publisher than a photocopy or microfiche from ERIC. The system produces four reference and referral databases as well as the bibliographic database of ERIC documents and journal articles. ERIC is committed to reach audiences that include practitioners, policymakers, and parents, as well as researchers. Components of the ERIC system responded to more than 42,000 requests from teachers and administrators in 1991, and several recent studies show that not only is ERIC recognized by teachers and administrators, but that its products are used and appreciated. (BBM)
2. Google scholar
Google Scholar is a freely-accessible Web search engine that indexes the full text of scholarly literature across an array of publishing formats and disciplines. Google Scholar index includes most peer-reviewed online journals of the world's largest scientific publishers. Google Scholar nonetheless claims to cover more websites, journal sources and languages. It is a nod to the scholars who have contributed to their fields over the centuries, providing the foundation for new intellectual achievements. In the other hand from one place, you can search across many disciplines and sources: peer-reviewed papers, theses, books, abstracts and articles, from academic publishers, professional societies, preprint repositories, universities and other scholarly organizations. Google Scholar helps you identify the most relevant research across the world of scholarly research.
3. Yahoo.com
(Yahoo!) respects the intellectual property of others, and we ask our users to do the same. Yahoo! has no responsibility for content on other web sites that you may find or access when using the products or services. Material available on or through other web sites may be protected by copyright and the intellectual property laws of the United States and/or other countries. The terms of use of those web sites, and not the Yahoo! Terms of Service, govern your use of that material.
4. Mamma
Mamma.com is a "smart" metasearch engine — every time you type in a query Mamma simultaneously searches a variety of engines, directories, and deep content sites, properly formats the words and syntax for each, compiles their results in a virtual database, eliminates duplicates, and displays them in a uniform manner according to relevance. It's like using multiple search engines, all at the same time. Mamma.com helped to introduce metasearch to the Internet as one of the first of its kind. Mamma.com's ability to gather the best search results available from top search sources and to provide useful tools to its users has resulted in its receiving multiple Honourable Mentions in the Best Metasearch