Next steps: programming, web development and data analysis

If you enjoyed making a web page do something, or finding the answer inside a table of numbers, this lesson is for you. Programming, web development and data analysis all ask you to give clear instructions to a computer and to check carefully that it did what you meant. You have already met variables, conditions, loops, HTML, CSS, JavaScript and spreadsheets. Here you will see how those pieces grow into three different directions and how to start a first project in each.

Three directions that share one habit

The shared habit is breaking a problem into small steps and testing each one. You used it in the Algorithm and flowchart lesson, and again when you read error messages and fixed a Bug. All three directions reward the same person: someone who is patient with errors, curious about why something happened and happy to look things up.

Programming

A programmer writes instructions that a computer follows, then tests them and fixes mistakes. The work can be anything from a small tool that renames photos to part of a large system. Many beginners start with Python because its grammar is easy to read, but the ideas you learnt in JavaScript carry across: variables, conditions, loops and functions look slightly different in each language, yet they do the same jobs.

The next ideas to learn are lists and dictionaries (ways to hold many values), reading and writing files, splitting a program into small functions and writing a few tests that check your functions give the right answers. You also need the habit of reading documentation, which you practised in the module on reading error messages.

• Skills you already have: variables, conditions, loops, functions, flowcharts, error messages and debugging.
• Skills to add: a second language, working with files, writing tests, using a Code editor well and keeping your code in Git.
• Beginner project: write a small program that reads a list of file names from a text file and prints a tidy version, for example all lower case with spaces replaced by hyphens. It must only print the new names; it must not rename any real file until you have tested it on a practice folder.
• Beginner goal: in three months, finish three small programs, each under one hundred lines, and keep them in a Git repository with a short README for each.

Web development

Web developers build the pages and applications that people use in a browser. The front end is what the visitor sees and uses: HTML, CSS and JavaScript. The back end is the part that runs on a Server, storing information and answering requests. You have built a simple page and published it, which is a real first step on the front end.

• Skills you already have: page structure, styling with the box model, flexible layouts, JavaScript events, form checks, browser developer tools, Git and publishing a Static site.
• Skills to add: responsive design on real phones, accessibility testing, a front-end tool or framework later, and eventually a back end with a database.
• Beginner project: build a three-page site for a community group, such as a choir or a small shop, with a contact form that only checks its fields in the browser. Test it with the keyboard alone, with zoom at 200% and on a phone. Publish it and write down what you learnt.
• Beginner goal: in three months, publish one site that passes your own accessibility checklist and ask two people to try it and tell you what confused them.

Data analysis

A data analyst turns raw figures into answers that people can act on. A typical question might be: which three products sold best each month, and did the weekend sales change after the shop moved? The work has four parts: collecting a Dataset, cleaning it (fixing typing mistakes, missing values and duplicates), calculating and charting, and explaining the result in plain words. The last part matters most: a correct number that nobody understands is of little use.

You can start with a spreadsheet. Data is often shared as a CSV file file, which a spreadsheet opens easily. The picture below shows the kind of small table you can practise on, using fictional sales.

• Skills you already have: spreadsheets, formulas, cell references, sorting and filtering, and charts.
• Skills to add: averages and ranges and how they can mislead, pivot-style summaries, cleaning messy data, choosing an honest chart, and later a language such as Python for larger files.
• Beginner project: find or create a small fictional dataset of about two hundred rows, such as a month of imaginary shop sales. Clean it, answer three questions with formulas and charts, and write a one-page report that a non-expert can understand.
• Beginner goal: in three months, finish two reports and explain, in one sentence each, what the data does not tell you.

A weekly routine that works

Five hours spread over the week beat one long session. A sensible pattern is three short sessions of about an hour for building, one session for reading and notes and one for showing your work to someone. Keep a notes file where you write what you tried, what failed and what the error message said. In three months that file becomes proof of how much you learnt.