Update for 15-03-22 22:30

tech/algorithms.wiki

@@ -58,6 +58,26 @@ Different ways to store and operate on data, with differing efficiency
 * [[machine_learning|Machine Learning]]
 * [[neural|Neural Networks]]
 
+== Programming patterns ==
+
+=== Creational ===
+
+* [[singleton]]
+* [[prototype]]
+
+=== Structural ===
+
+=== Behavioral ===
+
+* builder
+* factory
+* facade
+* proxy
+* iterator
+* observer
+* mediator
+* state
+
 == Common operations ==
 
 * [[gcd]] - Find the GCD of two numbers

tech/prototype.wiki

@@ -0,0 +1,8 @@
+= Prototype =
+
+This is a design pattern where we copy an existing object without making the
+code dependent on their classes.
+
+The general idea is sometimes we need an exact clone of an object. We cant copy
+the object exactly from the outside, as we dont know the private fields.
+Therefore, the object can implement a `clone` method

tech/singleton.wiki

@@ -0,0 +1,23 @@
+= Singleton =
+
+A singleton is a design pattern in which a class has only one instance, and
+that instance is globally accessable. This is often important for use in shared
+resources, such as a file, database connection, or logging application.
+
+== Implementation ==
+
+* Make the default constructor private, preventing other objects from using
+  `new`
+* Create a static creation method that acts as a constructor. This method calls
+  a private constructor and instantiates a static field, which is the
+  singleton. All further calls return a reference to this cached, static
+  object.
+
+== Use case ==
+
+* strict control over global vars
+* instance where a single instance of an object is required
+
+== Cons ==
+
+* Take special care to not instantiate several in a multithreaded enviroment