Email Extractor is free all-in-one email spider software. It is a lightweight and powerful utility designed to extract email addresses, phone numbers, skype and any custom items from various sources: websites, search engines, email accounts and local files. It is a great tool for creating your customer contact list.
This is the Linux app named Web Spider, Web Crawler, Email Extractor whose latest release can be downloaded as GITSTWebCrawler.jar. It can be run online in the free hosting provider OnWorks for workstations.
OnWorks is a free online VPS hosting provider that gives cloud services like free workstations, online AntiVirus, free VPN secure proxies, and free personal and business email. Our free VPS can be based on CentOS, Fedora, Ubuntu and Debian. Some of them are customized to be like Windows online or MacOS online.
The Screaming Frog SEO Spider is a website crawler that helps you improve onsite SEO by auditing for common SEO issues. Download & crawl 500 URLs for free, or buy a licence to remove the limit & access advanced features.
Web search engines and some other websites use Web crawling or spidering software to update their web content or indices of other sites' web content. Web crawlers copy pages for processing by a search engine, which indexes the downloaded pages so that users can search more efficiently.
The large volume implies the crawler can only download a limited number of the Web pages within a given time, so it needs to prioritize its downloads. The high rate of change can imply the pages might have already been updated or even deleted.
As Edwards et al. noted, "Given that the bandwidth for conducting crawls is neither infinite nor free, it is becoming essential to crawl the Web in not only a scalable, but efficient way, if some reasonable measure of quality or freshness is to be maintained." A crawler must carefully choose at each step which pages to visit next.
Junghoo Cho et al. made the first study on policies for crawling scheduling. Their data set was a 180,000-pages crawl from the stanford.edu domain, in which a crawling simulation was done with different strategies. The ordering metrics tested were breadth-first, backlink count and partial PageRank calculations. One of the conclusions was that if the crawler wants to download pages with high Pagerank early during the crawling process, then the partial Pagerank strategy is the better, followed by breadth-first and backlink-count. However, these results are for just a single domain. Cho also wrote his PhD dissertation at Stanford on web crawling.
Abiteboul designed a crawling strategy based on an algorithm called OPIC (On-line Page Importance Computation). In OPIC, each page is given an initial sum of "cash" that is distributed equally among the pages it points to. It is similar to a PageRank computation, but it is faster and is only done in one step. An OPIC-driven crawler downloads first the pages in the crawling frontier with higher amounts of "cash". Experiments were carried in a 100,000-pages synthetic graph with a power-law distribution of in-links. However, there was no comparison with other strategies nor experiments in the real Web.
Some crawlers may also avoid requesting any resources that have a "?" in them (are dynamically produced) in order to avoid spider traps that may cause the crawler to download an infinite number of URLs from a Web site. This strategy is unreliable if the site uses URL rewriting to simplify its URLs.
Some crawlers intend to download/upload as many resources as possible from a particular web site. So path-ascending crawler was introduced that would ascend to every path in each URL that it intends to crawl. For example, when given a seed URL of , it will attempt to crawl /hamster/monkey/, /hamster/, and /. Cothey found that a path-ascending crawler was very effective in finding isolated resources, or resources for which no inbound link would have been found in regular crawling.
The importance of a page for a crawler can also be expressed as a function of the similarity of a page to a given query. Web crawlers that attempt to download pages that are similar to each other are called focused crawler or topical crawlers. The concepts of topical and focused crawling were first introduced by Filippo Menczer and by Soumen Chakrabarti et al.
The main problem in focused crawling is that in the context of a Web crawler, we would like to be able to predict the similarity of the text of a given page to the query before actually downloading the page. A possible predictor is the anchor text of links; this was the approach taken by Pinkerton in the first web crawler of the early days of the Web. Diligenti et al. propose using the complete content of the pages already visited to infer the similarity between the driving query and the pages that have not been visited yet. The performance of a focused crawling depends mostly on the richness of links in the specific topic being searched, and a focused crawling usually relies on a general Web search engine for providing starting points.
An example of the focused crawlers are academic crawlers, which crawls free-access academic related documents, such as the citeseerxbot, which is the crawler of CiteSeerX search engine. Other academic search engines are Google Scholar and Microsoft Academic Search etc. Because most academic papers are published in PDF formats, such kind of crawler is particularly interested in crawling PDF, PostScript files, Microsoft Word including their zipped formats. Because of this, general open-source crawlers, such as Heritrix, must be customized to filter out other MIME types, or a middleware is used to extract these documents out and import them to the focused crawl database and repository. Identifying whether these documents are academic or not is challenging and can add a significant overhead to the crawling process, so this is performed as a post crawling process using machine learning or regular expression algorithms. These academic documents are usually obtained from home pages of faculties and students or from publication page of research institutes. Because academic documents make up only a small fraction of all web pages, a good seed selection is important in boosting the efficiencies of these web crawlers. Other academic crawlers may download plain text and HTML files, that contains metadata of academic papers, such as titles, papers, and abstracts. This increases the overall number of papers, but a significant fraction may not provide free PDF downloads.
Crawlers can retrieve data much quicker and in greater depth than human searchers, so they can have a crippling impact on the performance of a site. If a single crawler is performing multiple requests per second and/or downloading large files, a server can have a hard time keeping up with requests from multiple crawlers.
Cho uses 10 seconds as an interval for accesses, and the WIRE crawler uses 15 seconds as the default. The MercatorWeb crawler follows an adaptive politeness policy: if it took t seconds to download a document from a given server, the crawler waits for 10t seconds before downloading the next page. Dill et al. use 1 second.
A parallel crawler is a crawler that runs multiple processes in parallel. The goal is to maximize the download rate while minimizing the overhead from parallelization and to avoid repeated downloads of the same page. To avoid downloading the same page more than once, the crawling system requires a policy for assigning the new URLs discovered during the crawling process, as the same URL can be found by two different crawling processes.
While it is fairly easy to build a slow crawler that downloads a few pages per second for a short period of time, building a high-performance system that can download hundreds of millions of pages over several weeks presents a number of challenges in system design, I/O and network efficiency, and robustness and manageability.
Atomic Mail Sender is a professional email creator as well as a high-performance mass emailing software for your marketing campaigns. It enables you to manage email chains and send out business email marketing campaigns to an unlimited number of recipients. Sending bulk emails has never been so easy. Just download the email sending app directly from the site and run it. The Atomic Mail Scheduler will allow you to send HTML email messages faster than you can imagine. The app for sending email messages to email addresses works in multi-threaded mode which is capable of high-speed sending. You can send hundreds of email messages in less than a minute even with a slow internet connection. Before blasting your entire email list, you should validate it first with the Email Checker Tool. Otherwise, many of your emails could end up as spam. Personalize your newsletters, check for spam, remove invalid email addresses, and send an unlimited email broadcast. Are you looking for desktop mail apps? If so, choose the best one that fits your needs and send a free email online during the first 7 days!
Not sure if your extracted email addresses are truly valid? It would be wise to use our full package of list managers which can help you verify and structure your email lists. Not all mass email sender software applications can deal with address verification in these ways but this one can. Email management will become your favorite process in creating effective marketing campaigns for your company because this application will do all the work such as checking for syntax, domain names, and spam traps. Atomic Mail Verifier will help you avoid sending advertising campaigns to non-existent email addresses. So, if you have thousands of email addresses in your list, email campaign tools will find the fastest way to improve email list deliverability. Another good reason why you should use an email verification service is so that you can make sure you have authentic leads. The email validation tool verifies email addresses in three steps. This will allow you to check the authenticity of email addresses quickly and efficiently. An email validation service is conducted in multithread mode by using all the benefits of the valid email checker. Unlike other online email crawlers, our corporate email finder has a unique configuration that will allow you to control the extraction speed. This will protect your software and keep your IP address from being blocked. You can then enjoy the benefits of a fast and reliable email extractor by using online search engines while you savor your morning cup of coffee! 2b1af7f3a8