If you want to resize an image on a webpage, e.g., to have it display as
a smaller image on a webpage than it would based on the image's dimensions,
you can edit the image with a graphics editing application to create
a smaller version of the image or you can use
Cascading Stylesheets
(CSS). If you wished to apply the reduction in size to just one image
on the page, you could apply a style directly to the IMG tag for that
image. E.g., if image1 is
663 pixels wide by 307 pixels high, and you wanted to have the image
displayed as 75% of that size, you could use <img src="image1.jpg"
alt="Image 1" style="transform: scale(0.75)"> to have it display as
an image 75% of the actual dimensions of the image. E.g.:
Image 1 at full scale
Image 1 at 75% scale
Note: The image above is a photo of
Robert H. Goddard
with an A-series rocket circa 1935
In HTML 4, you could
use <table width="100%">.
In HTML 5, using width in
that way has been deprecated in favor of putting the width within a style
designation. If you use <table width="100%"> in an HTML 5
webpage and check the page with the W3C
HTML validation tool, you will see the message
" Error The width attribute
on the table element is obsolete. Use CSS instead." You can use the following,
instead:
<table style="width: 100%;">
The same is true for specification of the width of <td>
table elements. Under HTML 4, the following was ok:
<td width="33%" align="left">
In the above HTML code, the cell width could be specified as 33% of the
table width and text in a cell could be left-aligned with
align="left". Under HTML 5, though, both specifications are
considered obsolete and the following should be used, instead:
<td style="width:33%; text-align:left;">
If you need to center the text, you can use text-align:center,
instead. If you wish to vertically align an element in a table cell, such
as text or an image, in HTML 4 you could use the following:
<td valign="top">March 12</td>
In HTML 5, you can use the following instead of the above deprecated use of
valign:
I created this domain in April of 1997, a time when mobile device usage was
not common. HTML 3
was the version of the HyperText Markup Lanugage (HTML) in usage then with
HTML 4.0 not being
pubished as a W3C Recommendation until December of that year. In the past,
I used to add material to the site far more frequently. I haven't added much
to the site in the last few years and haven't made any significant changes
to the site for many years. Consequently, visitors viewing pages with large
images from a mobile device would see only the leftmost portion of those
images and would need to scroll right if they were using a mobile device
such as a phone. I finally added a few lines to the site's style.css
Cascading Style Sheets (CSS)
file today to have images be scaled down to fit the screens of mobile devices.
The lines I added are those below:
img {
max-width: 100%;
height: auto;
}
Those lines tell browsers that the maximum width of an image when it is
displayed within the user's browser shoud be no wider than the page's
width as it is displayed within that browser on that device. I added the
"height: auto;" to ensure that when images are resized that the height
is also adjusted to maintain the height to width ration of the original
image. Otherwise, some images might be distorted so that the image height
would be much greater in relation to its width than in the original
image. With the auto setting, the height to width balance remains such that
the image fits within the displayed page without appearing elongated.
With
HTML 4, centering the contents within a
div is simple. You
just use <div align="center">. E.g., if I wanted to
center the image and text below on a webpage, I could use the following
code:
If you wish to vertically align an image with text in
Hypertext
Markup Language (HTML) code that is compliant with
Cascading
Style Sheets (CSS) you can do so using <style="vertical-align:
position;"> where position is bottom, middle, or top.
E.g., if I want to align an image of the
direct current
symbol, which is a horizontal line over top of three shorter horizontal lines,
so that the image is vertically in the middle of the text, I could use the code
below:
If I used vertical-align: top, instead, the image would
appear as shown below where the text is aligned with the top of the
image:
24V 1500mA
If I used vertical-align: bottom, instead, the image would
appear as shown below:
24V 1500mA
If I did not specify a vertical alignment, the image would appear as
it did when I specified "bottom" for the vertical alignment as shown
below:
24V 1500mA
Though, in this case I could also have used the HTML code
⎓, instead, for the direct current symbol and avoided the
use of an image and the need to align the image with the text, though I
didn't realize that when I started using the image on a page for
power adapter for various devices.
The third specification of the
Cascading Style
Sheets (CSS) style sheet language,
CSS 3 provides support for
media queries, which
can adjust the display of information in a browser based on
screen resolution, e.g. smartphone screen vs. computer screen, the width
of the browser
viewport, etc. This is done through the use of
"@media,
which can be used in a style sheet or a style element included in the
<head> section of the HTML code.
Two parameters that can be used with @media are shown below:
max-width
The maximum width of the
display area, such as a browser window
min-width
The minimum width of the
display area, such as a browser window
With HTML 4, you can horizontally align an element in a cell in a
table using the align parameter, e.g.:
<td align="right"> to horizontally align text to the right
side of a cell. However, with HTML5, use of the align
parameter for horizontally aligning text within elements
of a table has been deprecated. E.g., if you check your
HTML code for adherence to the HTML 5 standard with the Nu Html Checker provided by the
World
Wide Web Consortium, you will see an error similar to the following
one displayed if you are using align in the HTML code for a table.
Thealignattribute on thetdelement is obsolete.
Use CSS instead.
From line 118, column 5; to line 118, column 22
</tr>↩<tr><td align="right">;<b>Vir
With HTML 4, you could center a table using
align="center".
<table align="center">
...
</table>
However, that method of centering a table is deprecated in
HTML5.
To center a table, which is a block-level element, in HTML5 using
a Cascading Style Sheets method, you can use
a style that includes margin-left: auto; margin-right: auto;
as shown below.
With HTML 4, you can horizontally center an image in a paragraph
using <p align="center">. E.g., the
image in the following paragraph would be cenered on the web page:
However, with
HTML5, use of the align parameter for horizontally aligning
a paragraph on a web page has been deprecated. E.g., if you check your HTML
code for adherence to the HTML 5 standard with the
Nu Html Checker provided by the
World
Wide Web Consortium, you will see an error similar to the following
one displayed if you are using align with the p (paragraph) tag.
Thealignattribute on thepelement is obsolete.
Use CSS instead.
From line 73, column 1; to line 73, column 18
tent -->↩↩<p align="center">↩<img src
1500mA
