Tuesday, October 30, 2012

Things web developers must know


The idea here is that most of us should already know most of what is on this list. But there just might be one or two items you haven't really looked into before, don't fully understand, or maybe never even heard of.
Interface and User Experience
  • Be aware that browsers implement standards inconsistently and make sure your site works reasonably well across all major browsers. At a minimum test against a recent Gecko engine (Firefox), a WebKit engine (SafariChrome, and some mobile browsers), your supported IE browsers (take advantage of the Application Compatibility VPC Images), and Opera. Also consider how browsers render your site in different operating systems.
  • Consider how people might use the site other than from the major browsers: cell phones, screen readers and search engines, for example. — Some accessibility info: WAI and Section508, Mobile development: MobiForge.
  • Staging: How to deploy updates without affecting your users. Ed Lucas's answer has some comments on this.
  • Don't display unfriendly errors directly to the user.
  • Don't put users' email addresses in plain text as they will get spammed to death.
  • Add the attribute rel="nofollow" to user-generated links to avoid spam.
  • Build well-considered limits into your site - This also belongs under Security.
  • Learn how to do progressive enhancement.
  • Redirect after a POST if that POST was successful, to prevent a refresh from submitting again.
  • Don't forget to take accessibility into account. It's always a good idea and in certain circumstances it's a legal requirementWAI-ARIA and WCAG 2 are good resources in this area.
Security
Performance
  • Implement caching if necessary, understand and use HTTP caching properly as well as HTML5 Manifest.
  • Optimize images - don't use a 20 KB image for a repeating background.
  • Learn how to gzip/deflate content (deflate is better).
  • Combine/concatenate multiple stylesheets or multiple script files to reduce number of browser connections and improve gzip ability to compress duplications between files.
  • Take a look at the Yahoo Exceptional Performance site, lots of great guidelines including improving front-end performance and their YSlow tool. Google page speed is another tool for performance profiling. Both require Firebug to be installed.
  • Use CSS Image Sprites for small related images like toolbars (see the "minimize HTTP requests" point)
  • Busy web sites should consider splitting components across domains. Specifically...
  • Static content (i.e. images, CSS, JavaScript, and generally content that doesn't need access to cookies) should go in a separate domain that does not use cookies, because all cookies for a domain and its subdomains are sent with every request to the domain and its subdomains. One good option here is to use a Content Delivery Network (CDN).
  • Minimize the total number of HTTP requests required for a browser to render the page.
  • Utilize Google Closure Compiler for JavaScript and other minification tools.
  • Make sure there’s a favicon.ico file in the root of the site, i.e. /favicon.icoBrowsers will automatically request it, even if the icon isn’t mentioned in the HTML at all. If you don’t have a/favicon.ico, this will result in a lot of 404s, draining your server’s bandwidth.
SEO (Search Engine Optimization)
  • Use "search engine friendly" URLs, i.e. use example.com/pages/45-article-title instead ofexample.com/index.php?page=45
  • When using # for dynamic content change the # to #! and then on the server$_REQUEST["_escaped_fragment_"] is what googlebot uses instead of #!. In other words,./#!page=1 becomes ./?_escaped_fragments_=page=1. Also, for users that may be using FF.b4 or Chromium, history.pushState({"foo":"bar"}, "About", "./?page=1"); Is a great command. So even though the address bar has changed the page does not reload. This allows you to use ? instead of #! to keep dynamic content and also tell the server when you email the link that we are after this page, and the AJAX does not need to make another extra request.
  • Don't use links that say "click here". You're wasting an SEO opportunity and it makes things harder for people with screen readers.
  • Have an XML sitemap, preferably in the default location /sitemap.xml.
  • Use  when you have multiple URLs that point to the same content, this issue can also be addressed from Google Webmaster Tools.
  • Use Google Webmaster Tools and Bing Webmaster Tools.
  • Install Google Analytics right at the start (or an open source analysis tool like Piwik).
  • Know how robots.txt and search engine spiders work.
  • Redirect requests (using 301 Moved Permanently) asking for www.example.com to example.com(or the other way round) to prevent splitting the google ranking between both sites.
  • Know that there can be badly-behaved spiders out there.
  • If you have non-text content look into Google's sitemap extensions for video etc. There is some good information about this in Tim Farley's answer.
Technology
  • Understand HTTP and things like GET, POST, sessions, cookies, and what it means to be "stateless".
  • Write your XHTML/HTML and CSS according to the W3C specifications and make sure theyvalidate. The goal here is to avoid browser quirks modes and as a bonus make it much easier to work with non-standard browsers like screen readers and mobile devices.
  • Understand how JavaScript is processed in the browser.
  • Understand how JavaScript, style sheets, and other resources used by your page are loaded and consider their impact on perceived performance. It may be appropriate in some cases to move scripts to the bottom of your pages.
  • Understand how the JavaScript sandbox works, especially if you intend to use iframes.
  • Be aware that JavaScript can and will be disabled, and that AJAX is therefore an extension, not a baseline. Even if most normal users leave it on now, remember that NoScript is becoming more popular, mobile devices may not work as expected, and Google won't run most of your JavaScript when indexing the site.
  • Learn the difference between 301 and 302 redirects (this is also an SEO issue).
  • Learn as much as you possibly can about your deployment platform.
  • Consider using a Reset Style Sheet.
  • Consider JavaScript frameworks (such as jQueryMooToolsPrototypeDojo or YUI 3), which will hide a lot of the browser differences when using JavaScript for DOM manipulation.
  • Taking perceived performance and JS frameworks together, consider using a service such as theGoogle Libraries API to load frameworks so that a browser can use a copy of the framework it has already cached rather than downloading a duplicate copy from your site.
  • Don't reinvent the wheel. Before doing ANYTHING search for a component or example on how to do it. There is a 99% chance that someone has done it and released an OSS version of the code.
Bug fixing
  • Understand you'll spend 20% of your time coding and 80% of it maintaining, so code accordingly.
  • Set up a good error reporting solution.
  • Have a system for people to contact you with suggestions and criticisms.
  • Document how the application works for future support staff and people performing maintenance.
  • Make frequent backups! (And make sure those backups are functional) Ed Lucas's answer has some advice. Have a restore strategy, not just a backup strategy.
  • Use a version control system to store your files, such as SubversionMecurial or Git.
  • Don't forget to do your Acceptance Testing. Frameworks like Selenium can help.
  • Make sure you have sufficient logging in place using frameworks such as log4jlog4net or log4r. If something goes wrong on your live site, you'll need a way of finding out what.
  • When logging make sure you're capture both handled exceptions, and unhandled exceptions. Report/analyse the log output, as it'll show you where the key issues are in your site.
Lots of stuff omitted not necessarily because they're not useful answers, but because they're either too detailed, out of scope, or go a bit too far for someone looking to get an overview of the things they should know. If you're one of those people you can read the rest of the answers to get more detailed information about the things mentioned in this list. If I get the time I'll add links to the various answers that contain the things mentioned in this list if the answers go into detail about these things. Please feel free to edit this as well, I probably missed some stuff or made some mistakes.

original source:  stackoverflow.com

Monday, October 8, 2012

AJAY BHAGESWAR NARKAR SIR PHYSICS TEACHER


दो लम्हे का जीवन है, एक क्षण उन्माद का, एक क्षण आह्लाद का, बस इतना ही जियूँगा 

"Maut kitne rang badle, dhang badle,


 Jab talak zinda kalam hai hum 


 Tumhe marne na denge"....


Today i heard that Ajay sir has no more ... Few people said that he was suffering


from cancer but other said that he under went an operation.


It's Very sad for such a young life with so much potential.


He leaves behind his wife and 2 daughters.


Its true that he was a bit arrogant and pompous at first glance but His


life story was full of persistent struggle and no doubt he was the most selfless


and bright teacher in Kanpur. He was more than a teacher of physics, in fact


he was a teacher of life. I really admire him as a person and love his soul in the true sense.


My deepest sympathy is there with his family.


I'm glad to see how much respect for him is there among 


his students.


He is still alive in us showing the right path.


He always said that believe in God that will bring you all 


the successes and strength in life.


In 1997-98, I went to get admission in his coaching 


classes.


Those days, He took Physics classes at Mahesh 


Chauhan's(IIT MATHS Teacher) house.


First time I saw him, classic old style spectacles and 


woodland shoes,shirt and Lee jeans.


On that day he learnt so many things. I still 


remember how he denied parents for admission 


because boy's father was chewing PAAN.


He was music lover, specially Kishore Kumar,


Still remember his song "musafir ho yarro".


One day He sent his wife to teach us Physics


and another day his daughter wrote a typical physics 


formula on board.



Classes's pin drop silence is still in my mind. 


On that time he used to mark signature in IE Irodov 


book's last page as a recieiving of 2nd instalment of 


tuition fee.( Still i have that book and signature).


He was crazy personality and self made figure.


He had holds record of slapping up to 1200 student and teaching 20 hours in a day.


He used to present self as A GOD among students and give cusses to them like devil. 


He is obsessed with self praising and mechanics. According to him, you can't play Holi


or go to movie because playing Holi or shopping or watching cinema for 2 hours will stop


you from getting into IIT.


I was slapped once by Sir. Still remember that day, whole class was punished for three hours,


after class we both discussed, He learnt me a new way to watch life.


His few famous words are:-


"Hum hum hain,baki pani kam hain..."

"Baangduon assignment pura hona chaiye , bhai logo kya bolte ho..."
"Ghansu PAAN wale ka BETA IIT me aa gaya ..."
"MOTI, Angothi ya mala se koi IIT me nahi ata ..."
"Maine teen saal se Diwali aur Dhasahara nahi manaya..."
"JO Log NAVRATRE KA 9 DIN KA FAST HAI VO KABHI IIT ME NAHI AYNGE..."

The Famous one is:


"Physics to ek bahaana hai tmhe insaan jo bnana hai".


He was real HERO..  Still when we think and trying to solve typical equations of life...


He helped us ... at least HE was Hero for students who learn Physics from him (1994 - OCT 2011) ....


Zindagi to bewafa hai ek din thukrayegi,

maut mehbooba hai
apne saath lekar jayegi.
mar ke jeene ke ada jo duniya ko dikhlayega
wo muqaddar ks sikandar ! janeman Kah layaga ...
http://www.youtube.com/watch?v=oNg9volIkYU