A slogan is a motto or a phrase which is used in context to express an idea or a purpose. Slogans are normally written, but they are crafted so that they are easy to chant, say, remember and so that they look visually pleasing when they are printed out. Slogans are often considered to be a form of expression, as opposed to them being a means to communicate with a specific or a desired audience.
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A tagline in some regards is considered to be a variation on a slogan. It is normally used for marketing purposes, and is a very crucial part of advertisements. The main goal behind a tagline, is to create a phrase which is memorable and one which can be easily remembered. It needs to be simple and it needs to store itself in the audiences memory, with a minimal number of repetitions. Some taglines become so popular, that they tend to become a part of pop culture and are used in normal day to day conversations.
This is why every company tends to try to hire experts to help them come up with taglines, so that they can have that lasting impact on the customers. Taglines also tend to get updated every now and then, to stay up to date with the change in global trends.
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