The search engine Google, for example, scrapes relevant websites at regular intervals and searches them for so-called keywords and backlinks in order to update and improve the search sequence. However, automated website visitors do not necessarily have to be a disadvantage for the company or website operator concerned. The IP addresses of these visitors can then be blocked with just a few clicks. This suggests that it is not human access. Simple web scrapers can be recognized, for example, by very short dwell times of less than one second or many pages accesses in a short time by one visitor. What do website operators think about scrapers?įor website operators, web scraping algorithms and other automated visits are comparatively easy to recognize via the web tracking tool. Beautiful Soup, for example, does not offer this feature, as it can only scrape the static elements of the website. For example, if you have to log in first, you can open the website in Selenium and also interact with it via Python code. The Selenium library is especially useful when interacting with the website must first take place in order to get the desired information at all. It goes beyond Beautiful Soup in that it also helps with subsequent data processing and data storage. Scrapy can be used for such applications too. The Python library Beautiful Soup is best suited for this, which we will also use in this example. The easiest way to do this is to hide the information you want to grab in the code that gets executed when the page is initially loaded. In web scraping, there are different levels of difficulty to get the desired data. Basically, they differ in how “deeply” they can scrape information from the page. Python provides various libraries that can be used for web scraping. Screenshot of the Source Code of Python Libraries for Web Scraping Otherwise, you can also right-click and then click Examine. If you are interested in how specific websites are built, you can view the source code of the open page in most browsers with the key combination Ctrl & Shift & i (MacBook accordingly Cmd instead of Ctrl). Everything that “pops up” afterward or is opened with a button without(!) loading a completely new page is programmed with JavaScript. Generally speaking, everything you see when you click the refresh button or when you come to a new page (with a different URL) is programmed with HTML and CSS. However, many also use JavaScript, in addition, to breathe life into the content. With the help of HTML and CSS, a large number of web pages can already be recreated. to define the font and font color or to specify the spacing between text elements. In addition, Cascading Style Sheets (CSS) are used to design the website, i.e. This is used, for example, to define which text sections are headings, to insert images or to define different page sections. The basic structure of any website is implemented with the help of Hypertext Markup Language (HTML). On w3schools there are also detailed tutorials on HTML, CSS, and JavaScript, where you can go further in-depth. In this article, we will try to cover only the most basic elements, without which this text would otherwise be incomprehensible. In order for us to understand and apply web scraping, we also need to look at the general structure and functioning of a website. Brief Introduction: Source Code of a Website
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