Web Page Extensions - Explained by Semalt Expert

23.05.2018

Web Page Extensions – Explained By Semalt Expert

First of all, let's de ne what a le type is. It's a certain speci cation (one of many) that describes the actual structure of a le. According to this structure, the le is stored, processed by programs and displayed. The visible part of le type for a user is le extension.

The le extension is a speci c sequence of characters (letters and digits), following the lename after the dot symbol "." and used to identify a type of le by programs and user. Seeing le's extension, the person or program understands what type of data is stored in a particular le, what features it has, what's necessary to run it.

It's worth noting that le extensions usually mean characteristic of a certain le, not le's belonging to any group.

For example, not all images have the same extension.

.html and .htm http://rankexperience.com/articles/article2455.html

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23.05.2018

HTML is a standard hypertext markup language of documents that form web pages. Files written in html usually have a self-titled extension. .htm is a le extension sometimes used for html les.

The difference between .html and .htm is only in one missing letter in a le extension. Earlier it was dictated by the need to limit the number of letters in le extension: old OS could read only three symbols. Today there is no real difference.

.php A le with .php extension is a text le with a code of script language PHP (Personal Home Page Tools). PHP language is widely used to develop web applications and web pages. Based on php- les the web server creates dynamic web pages. So, php- le is a program written with PHP and .php is its extension.

Web images A wide popularity for web graphics received two formats with extensions of the same name - GIF and JPEG. Their multifunctionality, versatility, small amount of source les with suf cient quality for a web page is what made them a standard for web images. There is also PNG format which is also supported by browsers when adding images.

However, the popularity of PNG is much inferior to GIF and JPEG formats.

GIF (Graphics Interchange Format) is a format of graphic les widely used when creating sites and posting on web pages. GIF uses 8-bit color and effectively compresses entire color areas while keeping the details of an image. GIF supports a frame-by-frame change of images which makes this format popular for creating banners and simple animations.

JPEG (Joint Photographic Experts Group) is another popular format for web images. JPEG supports 24-bit color and keeps brightness and shades of colors in photos unchanged. This format is used mostly for photos.

JPEG format can have .jpeg and .jpg extensions – same as with .html and .htm, all the difference is in one missing letter.

PNG (Portable Network Graphics) is similar to GIF. According to the developers, PNG uses an improved format for data compression.

So, to conclude, in most cases .gif les are animations and images requiring strong compression and small size, .jpg and .jpeg are photos and .png les are all the rest.

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