A picture is worth a thousand words "it is said, and rightly so! The very first thing that catches an eye is a picture before words and whenever someone dreams of a brand name usually the first thing that comes to their mind is its logo. A potent graphic can be very impactful and make a very lasting impression on the mind.
A graphic design is a form of visual communication. A human brain is evolved to decipher visual form of communication faster and can retain such visuals better and longer. Written communication requires learning and takes time to communicate and usually does not retain long enough. People usually do not read all that they see, but if the Design is eye-catching enough then it might make an impression enough to make them read or even without a single word, the idea can be communicated with just the IMG design.
If you wish to advertise then a graphic expression can get the idea of the product across or if you have a company then a logo can become the identity of your brand. A graphic can be used in advertising, to create a company logo, company brochure, pamphlets, leaflets, posters, standees, printing and stationary and even on a website.
Getting your graphic designed can be a very important decision and should not be taken trivially. You must consider getting it done from professional than doing it yourself as since they do it day in and day out, they are generally better than most lay persons. Plus there are far more things to consider when it comes to graphic designing, like not using kindly or by accident a design which has already been used and registered or trademarked. Infringing on intellectual property (IP) is a punishable offence! The design must also consider the product, brand and company and also the target audience. So when you seek the service of some professional Photoshop, make sure you spend enough time with them and explain every intricate detail to make sure the artist fully understands and does justice to the product and the target audience understands it easily and makes a lasting impression.
Getting the graphic designed by professionals saves you the time and efforts and is usually more polished and of greater quality than what a lay person is capable of creating. Plus, a lay person may not be conversant with the copyright laws and the registered and trademarked designs and may accidently infringe upon someone's intellectual property (IP).