It's been a busy week down the tech mines. We lost a good man in Windows XP, extracted a solid Samsung Galaxy S5 review and found a bad seam of internet danger when the two-year-old Heartbleed bug was discovered to be rotting secure websites from the inside out.

You'd be forgiven for struggling to keep up with what's what - but not for long. Here's the week's top tech news for your cribbing pleasure:

Bleeding hearts and password panic

The biggest threat to internet security to date was uncovered this week. A two year old hole took the 's' out of https and was dubbed, emotively, The Heartbleed Bug. Thousands of websites are potentially affected, meaning your passwords, emails, usernames, card details and more could possibly have been access by internet crims. Luckily, TechRadar is on hand: here are the seven things you need to know about Heartbleed, and robust advice on when to change your password.

RIP XP

Heartbleed emerged the very week that Microsoft retired support for Windows XP. COINCIDENCE? Well, yes. But still, it could cause a whole new set of security issues for XP users. What are your options? The best bet is to upgrade to a newer version of Windows - but you could take the opportunity to give Linux a try. Or just sack it all off and buy a Mac. Drastic measures, but here's what to do with your old XP PC if you do.

Phone fever

Time for some good news: the Samsung Galaxy S5 is here! It's on sale today and comes with a bunch of freebies to boot. In our official S5 review, Gareth Beavis proclaimed: "The Samsung Galaxy S5 can be defined by one word: evolution." It's powerful. It's competent. It's… more of the same. So how many stars? You'll have to click to find out.

Gear appears

Also on sale today is the Galaxy Gear 2 - has Samsung done the unthinkable and put together a smartwatch you might actually want to wear? It certainly looks that way - the Gear 2 has a cool design, it's easier to use than its predecessor and looks durable enough to handle even the toughest work-outs. Read our Galaxy Gear 2 review here.

Tweets of woe

Twitter's controversial new look started hitting profiles this week. It's got bigger images, more links, and looks a lot like Facebook. Prepare to be outraged and then move gently into acceptance over the next few weeks.

House of Ultra HD

Netflix's first 4K streams have gone live - the second season of House of Cards is now available in the eye-pleasing resolution. It's so good, in fact, that it may have ruined TV for our columnist Steve May forever - and the other downside is that you'll need one of 2014's pricey new 4K TVs to make the most of it.

The iWatch cometh

After some weeks of silence, the iWatch rumours are back with a vengeance. It's looking ever more likely that Apple will unveil its smartwatch in September alongside what we expect to be the iPhone 6.