When using Google as a search engine when typing your keyword google suggests certain keywords related to the keyword you typed. Google sugests popular 2-3 word keywords while typing in your search string. Google suggest increases the usability but it also effects SEO.
Google suggests changes the way we should optimize our webpages. With google suggest the chance of spelling errors reduces and some 2-word 3-word keywords will occur more often as they are suggested by google and who wouldn’t rather pick a keyword suggested then typing your own.
With google suggest it is not only more easy for the users but for the seo specialist as well, you get the different keywords you wanted on a silver plate and it also gives the amount of competitors for each keyword. Keywords with small amount of competitors might give you more chance to rank high for.