A QR code is a two-dimensional barcode that contains square shapes of varying sizes and orientations. It can contain significantly more data than traditional one-dimensional barcodes (with the parallel lines) like you'd find on items at a store. QR stands for "quick response" and you will often see it abbreviated as QRC as well.

Here are the ideal cover photo dimensions for each of these social networks. You can use any size, but these sizes will result in having the best aspect ratio and least loss in quality.

eBay can remove negative or neutral feedback on your seller account under certain circumstances. They may do this automatically depending on what their system detects, but often you will have to specifically request removal.

There are two ways to link to the full-screen version of a YouTube video. The first is using the popup player (now called the embed player), and the second is using YouTube's new TV-optimized website.

Facebook, Reddit, and other content sharing sites look for the og:image meta tag when deciding what thumbnail to use. Here's how you should use it effectively and also what size you should make it.

Below you'll find a chart showing the operating system usage data for H3XED in August 2014. The website caters to PC gamers and web developers primarily, with general information on YouTube, Facebook, and other websites.

I've been buying and selling on eBay since 2003 and have ran across many types of scams and unethical sellers. Here are some of the tactics these fraudulent sellers use most often to try and run scams. After reading these tips, you will be better equipped to buy on eBay (and other marketplaces), and will be able to spot many fake sellers and listings.

External and local IP addresses both serve the same purpose, the difference is scope. An external or public IP address is used across the entire Internet to locate computer systems and devices. A local or internal IP address is used inside a private network to locate the computers and devices connected to it.

Internet Protocol (IP) addresses are used by computers to find each other over the Internet. Think of it like a street address, but for computers and other networked devices.

The weakest link in a computer's security is the user. Bad habits and mistakes can prevent even the best anti-virus software from being effective, or can leave your email account in the hands of someone else with malicious intent.

The full-page video displayed on PayPal's homepage can slow down computers and be distracting if you're just there to log in. You can disable it easily using any popular ad blocking extension for Chrome or Firefox (µBlock, AdBlock Plus, etc). Just add these filters to your custom filter list:

Tired of the Google FIFA World Cup doodles? You may not want to see a new football/soccer doodle nearly every day for a month. If you already have a popular AdBlock extension for Chrome or Firefox, you can fix this easily using a custom filter.

The current unix timestamp is:

Type the below text into the input box. The clock begins when you start typing and ends when you type the final punctuation.