Example sentences
yín银háng行zài在chāo超shì市páng旁biān边。
The bank is next to the supermarket.
zuò坐wǒ我páng旁biān边ba吧。
Sit next to me.
About this word
旁 is "side" and 边 is "side, edge", so 旁边 is a doubled-up way of saying "the side", and it is the everyday word for "next to". The grammar is what matters: 旁边 is a location noun, so the thing it is next to comes first, as in 桌子旁边 or 学校旁边, or you frame it with 在, as in 他在我旁边. It never works as a preposition, so "beside the table" can never be 旁边桌子. For the other side of a wall, Chinese uses 隔壁, "next door".
The story behind the character
旁
旁 is 方 at the bottom giving the sound. The top part is a mystery, and Xu Shen said so out loud: he marked it 闕, which means "I do not know." His definition was 旁，溥也, vast, spreading wide. The "side" sense came later. A character with a confessed blank spot, still in daily use.
边
边 is 辶 (walking) with 力 on the right in its simplified form. The traditional 邊 carried a larger sound element on the right. Xu Shen defined it as 行垂崖也: walking along the edge of a cliff. So the side of a thing is, at root, the edge you do not want to step too close to.