Relampago del Catatumbo, Ologa, Venezuela

Thanks to its humidity, its elevation and the clash of winds from the mountains and the sea, the southwestern corner of Lake Maracaibo in Venezuela has the world's highest frequency of lightning activity (250 flashes per square kilometer per year).

More than 200 nights per year, with peaks in May and October, lightning flashes fill the sky -- sometimes 25 or more flashes per minute. To put that in perspective: The National Weather Service classifies anything over 12 strikes per minute as "excessive." Named for the Catatumbo River, which flows from Colombia in to Lake Maracaibo, the Relampago de Catatumbo, or Catatumbo Lighting, has become a highlight for travelers who spend their nights wide awake and wide-eyed watching the spectacle.

Old Faithful, Yellowstone National Park

Yellowstone National Park claims the highest concentration of geysers of any place on Earth. Geysers are hot springs with plumbing challenges that result in eruptions. More than 300 can be found throughout the park, and none is more famous than Old Faithful. In fact, Old Faithful is the reason Yellowstone was designated a National Park -- the first in the United States -- in 1872.

Its name comes from the perceived regularity of its eruptions, which occur every 55 to 120 minutes and last for two to five minutes. The spectacular eruptions remain a source of fascination for the more than 3.5 million people who visit Yellowstone each year. The fact that the eruptions aren't quite as regular as they might seem -- and that the mean eruption interval seems to be lengthening -- keeps geologists fascinated, too.

Moeraki Boulders, New Zealand

Large spherical boulders -- some measuring 12 feet in circumference -- are scattered on Koekohe Beach on the east coast of New Zealand's South Island. They formed millions of years ago on the ancient sea floor, collecting and hardening sediment and minerals around a core such as a fossil or a shell similar to the way oysters form pearls.

They're not the world's only examples of what geologists call septarian concretions. You can also visit the Koutu Boulders near Hokianga Harbour on the northwestern coast of New Zealand's North Island, for example. Yet the Moeraki Boulders are some of the world's largest. The particulars of their origin and what caused the distinctive cracks inside them are still being studied.

Surtsey, Iceland

When people try to convince you there's nothing new under the sun, direct them to the Icelandic island of Surtsey. Before 1963, it didn't exist. Then, an underwater volcano in the Westman Islands (Vestmannaeyjar) erupted, and when the activity settled down in 1967, what remained was an island where no island had been before.

Magnetic Hill, Moncton, New Brunswick

What could possibly cause an automobile to roll backward uphill without power? A magnetic force from within the Earth? Something even more fantastic? Since the 1930s, when the phenomenon of Magnetic Hill was discovered (and almost immediately promoted as a tourist attraction), people have been trying to figure out its riddle.

Blood Falls, Antarctica

Earth never stops surprising us. Every corner of the planet offers some sort of natural peculiarity with an explanation that makes us wish we'd studied harder in junior high Earth science class.

Some of these sites are challenging to get to; others are busy tourist destinations. They keep natural scientists searching for answers and the rest of us astounded by the secrets and mysteries the world continues to reveal.

Most people won't see Blood Falls in person, but even in photographs, the sight is arresting: a blood-red waterfall staining the snow-white face of Taylor Glacier. Glaciologists and microbiologists have sought to determine what causes the mysterious red flow. They've concluded that the source is a subterranean lake rich in the iron that gives the water its red hue. Stranger still, recent research has revealed microorganisms living 1,300 feet beneath the ice, sustained by the iron and sulfur in the water.

Microsoft removes store-blocking from Windows 10 Pro

Businesses running the professional version of Windows 10 can no longer block access to the Windows Store.

Following an update the function is now available only on the more expensive Windows 10 Enterprise version, as well as the Education edition.

Many firms try to prevent staff from downloading additional software as it can cause problems with existing programs and affect productivity.

Microsoft said it had made the change "by design".

"Windows 10 Enterprise is our offering that provides IT pros with the most granular control over company devices," the tech giant said in a statement.

"Windows 10 Pro offers a subset of those capabilities and is recommended for small and mid-size businesses looking for some management controls, but not the full suite necessary for IT pros at larger enterprises."

Educate staff

John Harrison, owner of Harrison IT services, said the change could cause problems for small businesses.

"Users like to change settings or try to install software by themselves. If they don't know what they're doing or don't have the appropriate experience, they can cause all kinds of issues," he said.

"You are going to have to educate staff, tell them not to use the Windows Store unless it really is relevant to the business. How do you manage that policy?"

In September 2015 there were 669,000 apps on the Windows Store, according toMicrosoft's own figures.

Microsoft says there are 300 million devices using Windows 10 one year after its launch.

On 29 July, a free upgrade offer for Windows users with earlier versions of the operating system will come to an end.