Logo was created in 1967 at Bolt, Beranek and Newman (BBN), a Cambridge, Massachusetts research firm, by Wally Feurzeig, Cynthia Solomon, and Seymour Papert. Its intellectual roots are in artificial intelligence, mathematical logic and developmental psychology. The first four years of Logo research, development and teaching work was done at BBN. The first implementation of Logo, called Ghost, was written in LISP on a PDP-1. The goal was to create a mathematical land where children could play with words and sentences. Modeled on LISP, the design goals of Logo included accessible power[clarification needed] and informative error messages. The use of virtual Turtles allowed for immediate visual feedback and debugging of graphic programming.
Primer paints may be oil- or water-based and are used to seal unpainted surfaces to prevent covering coats of paint soaking in. The appropriate type of primer should be used for the surface being painted - wood, metal, plaster or tiles. There are some 'all purpose primers' available which are designed for two or more of these surfaces. How Much Paint You Really Need. How much paint you will need to satisfactorily complete a paint project is determined by 2 factors. The first, paint coverage, is a familiar concept to most people. It simply concerns the square footage of surface area to be painted, and "paint coverage calculators" abound on the web. However, the second concept, paint color coverage, has a much more pronounced effect on how much paint will be needed and the cost of paint projects. Unfortunately, paint color coverage is a novel concept to many painters and, in fact, is poorly understood even by many professionals. Knowing the secrets of paint color coverage will allow you to reduce the number coats you have to apply and minimize how much paint you have to buy. HUE-VALUE-INTENSITY. Hue: Without getting too technical, and to put things into laymen's terms, hue is just another word for color. For instance, grass and leaves are two variations of a green hue.
Even if you don't need to apply a coat of primer before your new coats of paint, doing so will always save you money. Whether you use white or tinted primer, a coat of primer is always more cost effective for one simple reason: It is cheaper! In fact, primer may cost as little as half as much as standard paint. If you get it tinted the same as your paint, then it is cheaper by the coat. If you use white, as in the first scenario above, it will also minimize the number of coats of paint you have to apply. Either way it reduces how much paint you have to buy. Do you want to learn more about maximizing your paint color coverage, minimizing your paint usage, optimizing coats, and perfecting your primer? Special paints have been innovated from different consumer insights and brilliant paint technology that allows specific paints for specific needs. Home decor can range from paintings or wall hangings to room dividers, sculptures to vases, rugs, baskets to bowls, and pillow to throws. They are a wonderful way to surround yourself with the things that you enjoy. Accessories also act to bridge two seemingly disjointed colors and unify the room. The correct roller to use depends on the texture of the wall. On smooth walls you will need a 1/2" nap and on textured surfaces it will be more like a 3/4" - 1" nap depending on how rough the texture is. I always recommend a lamb skin, it will lay the paint off the best and provide maximum coverage. A roller pole is also great for saving your back, shoulder and arms from repetitious bending over and extension. If you will be using the roller for a couple of days, the same rule applies as with the brush, seal it in plastic completely to preserve it for the next day. Do not leave the roller submersed in paint or water over night, this will cause premature failure, by releasing the skin from the hardboard backing it is attached to. If you will be rolling a rough texture, like a stucco, make sure to purchase a roller frame (arm) that is sturdy and will hold up to constant applied pressure.