Sources: Text Tutorial Espresso Course Main Android Terms An activity is one screen of an app. In that way the activity is very similar to a window in the Windows operating system. The most specific block of the user interface is the activity. An Android app contains activities, meaning one or more screens. Examples: Login screen, sign up screen, and home screen. An activity in Android is a specific combination of XML files and JAVA files. It is basically a container that contains the design as well as coding stuff.

Udemy Course Blog Kotlin features Static Typing: Like Java, variables can only be assigned values that match their type. var m : Int = 12 m = 10 // ok m = "twelve" // error!

Useful things Create a list from range list = [x for x in range(5,100,2)] // (begining, end, step) print(list) Create a dictionairy from 2 lists list = [x for x in range(5,20,2)] listB = ["apple", "banana", "pear"]

Selenium Architecture

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# GIT commands

SQL is a standard language for storing, manipulating and retrieving data in databases. Relational vs Non-relational database Relational databases are structured. You have tables and these tables may have dependencies on each other, or relationships. A database for a store will have a table for customers and one for orders. These two tables are related, because an order is made by a customer. Non-relational databases are document-oriented. This so called document type storage allows multiple 'categories' of data to be stored in one construct or Document. So using the previous example, a Customer document, would have the customer's information, a sub-category for all their orders, etc. Relational SQL Databases A relational database uses SQL. This is a fairly rigid and standard way of storing data using tables, columns and rows. Data is defined in a table which is usually atomic in nature; this means that a table should really only store data records on one entity or object at a time. Eg. A Table Customers should ONLY be storing customer records.

A shell is a program that receives commands from the user and gives it to the OS to process, and it shows the output. pwd It gives us the absolute path, which means the path that starts from the root. The root is the base of the Linux file system. It is denoted by a forward slash / Air-Alena:~ alenaagapova$ pwd /Users/alenaagapova ls and ls-a ls — Use the "ls" command to know what files are in the directory you are in. You can see all the hidden files by using the command “ls -a”.