Two regular expressions that are used in Japanese for conveying similarity, and dissimilarity are と同（おな）じで ‘the same as (A)’, and と違（ちが）って ‘different to (A)’. While both of these structures use the 格助詞（かくじょし） (case marking particle) と to mark (A), 同（おな）じ is a noun, while 違（ちが）って is the て form of the う - Verb, 違（ちが）う. Due to this, the 助動詞（じょどうし） (auxiliary verb) だ is required after 同（おな）じ, in order to link (A) and (B). だ will appear in its 連用形（れんようけい） (conjunctive form).
Both と同（おな）じで and と違（ちが）って will be preceded by a noun or noun phrase, before the (B) part of the sentence will describe the similarity/dissimilarity.

• 彼（かれ）は僕（ぼく）と同（おな）じで、猫（ねこ）アレルギーです。
  Just like me, he is allergic to cats.
• 母（はは）も私（わたし）と同（おな）じで、アウトドアが好（す）きです。
  Just like me, my mother likes the outdoors.
• 私（わたし）は弟（おとうと）と違（ちが）って、本（ほん）を読（よ）むのが大好（す）きです。
  Unlike my brother, I love to read books.
• 彼女（かのじょ）は私（わたし）と違（ちが）って、遊園地（ゆうえんち）が苦手（にがて）です。
  Unlike me, she does not like amusement parks very much.

In this structure, as the 接続助詞（せつぞくじょし） (conjunction particle) て, has a similar role to the conjunctive form of だ (で), both expressions are simply stating that (B) is existing in a state of ‘having sameness’, or ‘having difference’ with (A).