The idea is that you are developing a website locally using git, and you want to be able to easily push to your live site with git. We will set up a remote repository on your server, and push to it.

Let’s say you have your local repository already set up. Log on to your remote machine. Navigate to a directory where you want to keep your repository. This does not necessarily need to be the same location as your code, and you actually probably want it to b e a different place.

### On the remote machine
corn03:/afs/ir/group/paperless2> mkdir repo.git && cd repo.git
corn03:/afs/ir/group/paperless2/repo.git> git init --bare
Initialized empty Git repository in /afs/ir.stanford.edu/group/paperless2/repo.git/

The way this is going to work, is that we are going to create a post-receive hook. A post-receive hook means you can run some script after this repo has received a push. What we are doing here is checking out the current gode to some directory, which we define as the GIT_WORK_TREE. You can make the GIT_WORK_TREE wherever you want. Then we make the script executable.

corn03:/afs/ir/group/paperless2/repo.git> cat > hooks/post-receive
#!/bin/sh
GIT_WORK_TREE=/afs/ir/group/paperless2/cgi-bin git checkout -f
corn03:/afs/ir/group/paperless2/repo.git> chmod +x hooks/post-receive

Now, on your local machine, add the remote you want to push to. On this first one, make sure you include the branch you are including, like master.

## Locally
> git remote add web ssh://jkeeshin@corn23.stanford.edu/afs/ir/group/paperless2/repo.git
> git push web master

For any future updates

> git push web

It’s pretty basic, easy to use, and works for lightweight deployment for a site by yourself or with a few other people.

The only issue I had was one time, my internet connection went down in the middle of deployment and the git process crashed. Then the next time I tried to push, nothing happened. After a little bit of searching, the fix was that there was a file “index.lock” that was created, and once we removed that file, it worked again.

Hobson’s choice: the choice of taking either that which is offered or nothing; the absence of a real alternative.
Origin: 1640–50; after Thomas Hobson (1544–1631), of Cambridge, England, who rented horses and gave his customer only one choice, that of the horse nearest the stable door, from dictionary.com.

I just joined another site yesterday. Or it was an app, I don’t really remember. It doesn’t really matter what it was. But this site had terms and conditions that you had to accept before using it. If you are just a general internet user, there is really nothing you can do about terms and conditions. If you want to use this site or app, you have to accept them. And if you don’t agree with them (and my guess would be in most cases, you would always be able to find something you don’t agree with), you simply can’t use the site.

This is the classic case of a Hobson’s choice, where there appears to be a real choice between two alternatives, but one of the options isn’t really an option.

Consider a case where you are at work and the boss wants you do to something, and he says to you: “Either you can do this, or you are fired!” In this case, you have “a choice”– you can either do this task or not. But assuming you want to keep your job, you are left with no real alternative, and similarly very little bargaining power.

The end users on the internet face this on basically every site you join. There are way too many terms and conditions for it to be at all feasible and reasonable for you to read them. Almost all sites present terms and conditions in a way where they *expect* you not to read them, but you *have* to agree to them to use the site. The sad state of affairs is that users *have* to a agree to a term sheet that they *almost certainly* never read. Many sites have terms and conditions hidden at the footer of their site that you implicitly agree to just by being there.

If I had to guess I would say that way less than 1% of Apple users read their terms and conditions sheets. I would be very curious to know that number.

So that’s about it. If you want to use the internet at all, just accept the fact that you had to agree to all these really stupid contracts that you have never read.

Today, I want to write about “clients” and “servers.” These are words that are used a lot in describing basic parts of the internet, so here is the answer:

The definitions go hand in hand, and so that is why I will introduce them together.

The client is someone that requests information server. The server is the one who responds to the requests.

If you think about it like a restaurant–when you go, you sit down at your table. You are the “client,” you can order whatever food you like. The waiter or waitress is your “server,” they respond to your requests.

In terms of the internet, you are the client. When you want to visit a webpage, say google.com, you make a request to get their webpage, and one of Google’s servers responds with the webpage.

When people talk about servers they can mean a million different things, but usually they are referring to some computer, (or part of a computer), that is responsible for “serving” up their website, or responding to the different clients who are requesting it.

“Client” and “server” go hand in hand with another pair of words: “front-end” and “back-end.” Front-end is the client-side, or the place where you, the end-user, is. Back-end is the server-side, where the website’s big computers and data-centers are. Now if I told you that “php is a server-side programming language”–you can start to decode that phrase.

A programming language is just the way that you tell a computer what you want it to do. You run programs on your computer, like a web browser, or maybe iTunes. These are programs. Someone or a group of people built these programs, and the way they did it was by using a programming language.

There is a famous first program that people write, called “Hello World” where you just try and get the program to print out “Hello World.” Here is an example in a programming language called C:

#include <stdio.h>

int main(){
    printf("Hello World");
}

Theres a lot of random stuff here, a lot of random syntax to get the program to run, but the basic idea is that this will output “Hello World” when you run it.

In another programming language called python, if you want to print hello world you just write:

print "Hello World"

Different programming languages have different ways of telling the computer to do things. Many math operations also carry over, so for example you could add two numbers in python with:

print 5 + 10

There is wayyyyyyyyyyy more to programming languages. There is a specific legal way to write things in programming languages, and that is called the syntax. There are lots of other ways to classify and talk about programming languages, but that is for another time.

So the first question is, what is binary? Binary is a base 2 number system. That might sound confusing at first, so I’ll try and compare it to a few examples you may be familiar with.

Take the number 2537. Two-thousand, five hundred, and thirty-seven. What that really means is two “thousands,” five “hundreds,” three “tens,” and seven “ones.” Our normal number system is in base-10, or decimal. What that really means is that each place stands for a power of ten. So “ones” is 10^0, “tens” is 10^1, etc.

When we talk about base-2, instead of our places standing for powers of 10, they stand for powers of two. So instead of “ones,” “tens,” and “hundreds,” we have “ones,” “twos,” and “fours.” “ones” is 2^0, “twos” is 2^1, “fours” is 2^2. (The notation X^Y means X to the power Y, so 2^3 is 2*2*2.)

If you look at the base-2 number 1011, what we have is a 1 in the “eights” place, a one in the “twos” place and a one in the “ones” place. Adding that up we get 8+2+1 = 11. The thing about binary is you only have ones or zeros, which is very easy for a computer to represent–it’s kind of like on and off.

One binary digit, a “one” or a “zero” is called a bit. Basically computers store everything in bits. All information is somehow represented in bits. It’s kinda crazy, but that’s what it is. So now you know.

IP Addresses continue the very interesting series of names that we find on the internet. For us, they are sort of the end of the line when it comes to the internet and names. Our friend sends us a link, a URL of another webpage. That URL is the full human readable location of that thing on the internet. Part of that url is the domain name, which refers to a computer or a bunch of computers somewhere. But unfortunately, computers don’t really read English, and when you say “Go to thekeesh.com,” it really doesn’t know where to go.

There are a few steps in between that we will talk about later, but basically what happens is that you say “thekeesh.com” and it says: “173.230.152.171″

So that’s my real address on the internet. It’s an IP address, or an Internet Protocol Address.

I was going to make my own image like I’ve been doing in the past, but just found Wikipedia’s and it is pretty good.

So here’s an IP address broken down. It’s four numbers between 0 and 255 (8 bits, but we’ll get to that later). To be honest, it doesn’t really matter here what the numbers mean. Basically you can think of the IP Address as being the address of a domain name on the internet that computers understand.

The Big Issue

Basically, the internet has gotten really big recently, and we are running out of these numbers. Read more about it here. So people redesigned IP adresses to give us way more addresses. They are 128 bit (we will talk about that more later), but that means that there are “2^128 (approximately 340 undecillion or 3.4×1038) addresses,” according to Wikipedia. That is a huge number. We are much less worried about running out with IPv6.

So the moral of the story: An IP Address is the number assigned to a computer that is connected to the internet. Everything connected to the internet gets one, phones and printers too!

URL stands for Uniform Resource Locator, but it just means a specific thing on the internet. This may refer to a specific page on my blog, or a specific image you found off Google. Some people who get mad about technical things say that we should really call it URI (Uniform Resource Identifier), but the difference isn’t a big deal here, and most people call things URLs.

Here is an example URL: http://thekeesh.com/?s=domain+names

This has most of the parts of a URL that we care about.

The part that says “http://” or “https://” is the scheme or the protocol. That is just telling us something about the way everything is sent. We’ll talk more about that later. The part that says “thekeesh.com” or www.facebook.com is called the domain, like we talked about before. The part after the domain name but before the question mark is called the “path,” as you can see in the Facebook url, the path is “/jkeesh.” The part starting with the question mark is called the query string and gives a little more information to the URL. I will talk more about query strings in a later post.

That is what a URL is. You may still be confused on the parts of a URL, but we will go into more depth on those later. Whenever you send a “link” to someone, you really send them the URL. It’s just a specific thing on the internet, and the URL is the full name that refers to it.

www.google.com
www.facebook.com
www.thekeesh.com

These are all domain names. But so is

mail.google.com

and as you can see from this short list, it’s slightly different. It has a different part at the start, which we call a “subdomain,” or something more specific.

On the far right we have the “top level domains,” (or TLDs), like com, edu, gov, and org. (Don’t look now but there is a new xxx TLD.) Then we get more specific with “google,” and even more specific with “www” or “mail.” These names are just ways to identify sites on the internet.

http://www.google.com

There’s also one more funny part in this one, which is “http,” which is the protocol. This is not technically part of the domain name, but we’ll talk more about this in a later post.

The main point here is to understand that there are such things called “domain names,” and they are how you identify websites on the internet. There are different parts and they get more specific going right to left.

But I’ve noticed many people are confused on what the distinction between the “browser” is and what the “internet” is, and if you aren’t familiar with computers, it’s easy to confuse the two. A long time ago, I bet most people thought that AOL was the internet, but we have come a ways since then.

Ok, so here it is. What is a web browser? A web browser is just a program that runs on your computer that lets you access different websites on the internet. If you don’t know what a “program” is, it is just something running on your computer that is doing something for you.

That’s all there is to a browser. It’s nothing too complicated, but let’s try and clarify it with some analogies.

Imagine you are making a phone call to your parents. You could really call anyone through this whole network of phones, but you call a specific person. The phone that you use is your access point to all of the other people in the phone network, but the phone is not the network. In a similar way, the browser is your access point to all of the different websites on this network, but the browser is not the network.

While we can think of the internet being on a lot of different computers, the web browser is really just on your own computer. And like there are many types of phones you can buy to access the phone network (a flip phone, an iPhone, an Android phone), there are different types of browsers you can use to access the internet. Think of different browsers like different brands of phones.

Browsers are generally free, and have adopted many similar features, even though they don’t really have an exact specification of what they need to be. Some browsers are Google Chrome, Mozilla Firefox, and the evil Internet Explorer. For me, Internet Explorer feels like using a broken abacus when everybody else is using a calculator. Which is a bummer because so many people still use it (according to here and here). I’d recommend Google Chrome, and you can see raunk for the list of Best Web Browsers.

Here is a quick tour of some important parts of the browser. There is the address bar, where you can type the site you want to go to. There is the bookmark bar where you can save favorite sites. There are tabs so you can have many sites open at the same time. And I’ve highlighted the settings icon in Chrome for reference.

So that’s mainly it. A browser is a program that is on your computer that lets you access the internet. It does a lot of fancy stuff like running javascript and rendering HTML and CSS and a lot more, but that’s not really what this post is about.

If you have any comments, let me know!