Do you want to know how to create your own calculator using HTML and Javascript? While you can use prompt and alert boxes like this:
<!DOCTYPE html>
<html>
<head>
<title>Calculator</title>
</head>
<body>
<h1>Calculator</h1>
<script>
var x = prompt("Type the first number here");
var y = prompt("
This summer I went on a trip to crater lake national park. While the lake itself has no birds, the pine forests surrounding the lake are filled with birds. Like all forests, however, it is very hard to see the birds, as most forest birds are found in the tops of the trees. Luckily, I managed to glimpse a few nutcrackers foraging in the treetops. Nutcrackers in the wild eat a variety of things, including insects, small mammals, berries, nuts, and even dead animals!
Nutcrackers are found across western North America, from California and Oregon north to Alberta and as far south as Western Mexico. The nutcracker is identified by its weird call, sounding like waaaa-waaaa. Once you here a call, look for the tree that the call is coming from. Since nutcrackers hide in the denser parts of the pine forests, it can be hard to spot them. However, if you spot a grey and black bird hopping around the branches, it is a nutcracker.
In addition to the nutcracker, I spotted a bunch of other birds around the pine forests, including Grey jays, American robins, and juncos. Later, when we were driving from crater lake to our hotel, I spotted 12 species of birds. Since we were in more open habitats, I spotted different species of birds. In the vast fields that were used for cows to graze on, I spotted flocks of blackbirds feeding in the grass. A bit further on a Black-billed magpie flew across the field. Soon we had reached some pine forest, although it was less wooded than the forest near crater lake. Here I saw large swift-like birds flying through the forest. At first they seemed a bit peculiar, but I soon realized that they were Common nighthawks. While they are common, they are neither nocturnal nor are they hawks. Nighthawks are actually part of a group of crepuscular (active during evening) birds called nightjars. The nightjars are found worldwide.
The unfortunate part about the birds I saw was that I could not get a picture of any of them, as we were driving and the picture would have been very blurry had I taken a photo. However, I now have several photos of the nutcracker, one even in a tree right next to crater lake!
Above: This Clark’s nutcracker photograph was taken in the forests of Crater Lake on our trip. I had been wanting to see it, and luckily we spotted it when we parked our car on the road to eat lunch.
In this post I will explain how to create a very simple HTML and Javascript quiz that uses functions. A function is a set of code in Javascript that does a specific task. Below is a example of a function:
function helloworldFunction()
alert(“Hello world!”)
When you open this code in a browser, the page alerts “hello world!”
However, to make the function interesting, you can add it to an HTML button. For example:
<button onClick=“helloworldFunction()”>hello world button</button>
When you click the button, the webpage alerts you, saying “hello world”. The above code is the basis for building a function quiz. Below is the code required to make a function quiz. (Note: the questions and answers shown here are examples, and you can make your own questions and answers. Also, the CSS styling can be made up as well. I used a black background with a border of solid blue and colored the text white.
FUNCTION QUIZ code example:
<!DOCTYPE html>
<html>
<head>
<font color=“#ffffff”><title>Quiz</title>
<h1>Quiz</h1>
</head>
<body>
<style>
background-color: #000000;
border: 2px solid blue;
</style>
<p>1. Which one of these codes is the HEX code for orange?</p>
<button onClick=“wrongFunction()”>#ffffff</button>
<button onClick=“correctFunction()”>#FFA500</button>
<button onClick=“wrongFunction()”>#FF0000</button>
<button onClick=“wrongFunction()”>#000000</button>
<p>2. How many species of birds are found in North America?</p>
<button onClick=“correctFunction()”>500</button>
<button onClick=“wrongFunction()”>125</button>
<button onClick=“wrongFunction()”>213</button>
<button onClick=“wrongFunction()”>100</button>
<p>3. Jays and magpies make up which one of these bird families?</p>
<button onClick=“wrongFunction()”>Ardeidae</button>
<button onClick=“wrongFunction()”>Cotingidae</button>
<button onClick=“wrongFunction()”>Hirundinidae</button>
<button onClick=“correctFunction()”>Corvidae</button>
<p>4. The apple is native to which one of these continents?</p>
<button onClick=“wrongFunction()”>Europe</button>
<button onClick=“wrongFunction()”>North America</button>
<button onClick=“correctFunction()”>Asia</button>
<button onClick=“wrongFunction()”>South America</button>
<p>5. What is the name of the ecozone comprising of Europe, western Asia, and Northern Africa called?</p>
<button onClick=“correctFunction()”>Palearctic ecozone</button>
<button onClick=“wrongFunction()”>Neotropical ecozone</button>
<button onClick=“wrongFunction()”>Indomalayan ecozone</button>
<button onClick=“wrongFunction()”>Australasian ecozone</button>
<p>6. What Palezoic period did blastoids go extinct in?</p>
<button onClick=“wrongFunction()”>Ordovician</button>
<button onClick=“wrongFunction()”>Carboniferous</button>
<button onClick=“wrongFunction()”>Devonian</button>
<button onClick=“correctFunction()”>Permian</button>
<p>7. What is the name of the highest mountain in South America?</p>
<button onClick=“correctFunction()”>Mount Aconcagua</button>
<button onClick=“wrongFunction()”>Mount Huascaran</button>
<button onClick=“wrongFunction()”>Mount Everest</button>
<button onClick=“wrongFunction()”>K2</button>
<p>8. The Netherlands have a large population of what native waterbird, named for its unusual bill?</p>
<button onClick=“wrongFunction()”>Grey heron</button>
<button onClick=“wrongFunction()”>Common eider</button>
<button onClick=“correctFunction()”>Eurasian spoonbill</button>
<button onClick=“wrongFunction()”>Common scoter</button>
<p>9. What time period did Archelon, a giant sea turtle, live in?</p>
<button onClick=“correctFunction()”>Cretaceous</button>
<button onClick=“wrongFunction()”>Jurassic</button>
<button onClick=“wrongFunction()”>Paleogene</button>
<button onClick=“wrongFunction”>Neogene</button>
<p>10. Which one of these birds are the New world vultures closely related to?</p>
<button onClick=“wrongFunction()”>Old World vultures</button>
<button onClick=“correctFunction()”>Storks</button>
<button onClick=“wrongFunction()”>Hawks and eagles</button>
<button onClick=“wrongFunction()”>Falcons</button>
<script>
function correctFunction() {
alert(“Correct!”)
}
function wrongFunction() {
alert(“Wrong”)
}
</script>
In the code above, the HTML and CSS style the page, and the Javascript adds interactivity to the buttons created using HTML. The CSS code sets the styling of the page (in this case, a black background with a blue border), and the HTML make the questions as well as the answer buttons. The HTML code is linked to the Javascript code through the onClick property. The Javascript code includes the correct and wrong functions and the javascript alerts for correct and wrong selected answers.
A white-throated kingfisher sits perched on a tree in Chennai, India.
The white-throated kingfisher is found all over the Southern part of Asia, from Turkey to the Philippines. It has four subspecies, with the one in the photograph most likely being H. c. fusca. I saw this bird perched in the trees, apparently trying to eat some small creature (probably either a lizard or a fish.) However, tree shots of birds are very hard to get, so the picture only shows the body of the bird and the beak as well.
Kingfishers are often thought of as small waterbirds that hunt fish, but this is far from the truth. Most kingfishers are hunters of many small creatures, including lizards, small mammals, and even some small birds! The White-throated Kingfisher is a predator of several small birds, including sparrows and munias (a kind of tropical Old World bird that resemble sparrows).
The Kingfishers used to be grouped all as one family: the Alcedinidae. However, now they are split into three families – the Alcedinidae (river kingfishers), Halcyonidae (tree kingfishers, the family the White-throated kingfisher belongs to), and Cerylidae (water kingfishers). The Alcedinidae includes the smaller species which mainly eat insects and small fish. The Halcyonidae is medium-sized, and these kingfishers are called tree kingfishers because they are most often found in dense tropical woodland or forest close to a body of water. The last group, the Cerylidae, includes the giant kingfishers, which prey on large aquatic and semi-aquatic animals, like crabs and frogs.
The season for winter migrants was over in the San Francisco Bay. Scoters, gallinules, and other birds that came for the winter began disappearing from the reed marshes and pools. Now very few birds there, among them Mallards, a pair of Gadwall, and a few grebes, including Pied-billed and Western.
In the mudflats there was a large grass-covered island, which situated a large Cackling goose, which was nearly as big as the island itself. However, there were two black-and-white birds that happened to be resting nearby. When I looked at the photo that my dad took of them, they had a orange-and-black bill, and the upper bill was shorter than the lower bill. This could only mean that it was one bird – the Black Skimmer.
The San Francisco Bay is the northernmost range for this species of skimmer, which can be found year-round in the bay. The ones I saw were beginning to molt into their summer breeding plumage.
The Black Skimmer may look like a tern from far away, however, look for the length difference between the lower and upper bills.
It uses its peculiar bill for its hunting technique. When hunting for fish, it uses it bill to cut through the water. When the bill touches anything solid, it snaps shut, catching any fish in the process. However, this technique has problems. If there is some wood in the water, the skimmer may mistake that for fish, and that is the cause for many skimmers to have broken bills.
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American coot (Fulica americana) at Shoreline park, Mountain View, California.
The American coot is one of the most common gruiform birds in North America. The common gallinule may be the most common Rallidae bird in the world, but the American coot far outnumbers it in some parts of North America.
American coot is all black in color, excluding the white frontal shield and beak. Also, if you look very closely on adults, you may also see a small patch of red on the forehead.
American coots are part of the diverse genus Fulica (coots). The coots are found worldwide, although they reach their greatest diversity in South America. The American coot is the only coot that makes it to North America.
It is roughly chicken-sized and quite similar to the Common gallinule (Gallinula galeata). I have added a list of comparisons between the American coot and common gallinule in the Common gallinule article.
A large group of American coots slowly swim across the water. Their white frontal shields are easily seen in the late afternoon sun. Suddenly, another bird is spotted. It looks very similar to a coot, yet it has a red frontal shield. Like the coots, it is swimming around in the water. What is it? It’s a gallinule, specifically the Common gallinule (Gallinula galeata).
The common gallinule, as it’s name suggests, is one of the most common gruiform birds in North America. In fact, it is the most widespread Rallidae bird in the world, far outnumbering the coots, its close relatives. There are two species of gallinules in North America, the Common and the American purple. The latter is a brightly colored wading bird that inhabits the swamps and water-logged forests of the Southeast.
In terms of size, Common gallinules are roughly chicken-sized. In fact, they resemble gamebirds more than the secretive and water-loving rails. However, no North American gallinaceous birds have bright red beaks with yellow tips. Also, it is very rare to find a Common gallinule far from water, while many species of gamebirds in North America live in prairies and forests, sometimes far from water.
The common gallinule and the American coot look very similar, and are closely related. However, there are some notable differences. Below is a chart of each bird’s identification, so that they can be distinguished.
American coot:
Common gallinule
The House sparrow is probably, along with the American crow and mallard, one of the most familiar birds in North America. It is a non native resident, the first birds being introduced to New York in 1851. Since then, it has spread throughout the continent. House sparrows are very common, yet they have been declining in North America. The House sparrow is also declining in its native range, Europe and Asia, due to toxins. This species is also shot in places where it is not native, because it is an aggressive bird which displaces native birds, like the American robin, by stealing their food and invading nesting holes.
A very interesting fact about the house sparrow is that this species set the world record for making the most dominos fall. In 2005, a few days before Domino day (a day where people would try to set the world record for making the most dominos fall), a house sparrow crashed into the building where Domino day was held, and flew into a pile of four million dominos, causing twenty-three thousand of the dominos to fall. It had set a world record! However, people caught the sparrow and shot it, which was very sad.