Parede vs. muro
While both words translate to "wall" in English, the distinction between muro and parede in Portuguese is strictly defined by location and function. Generally, parede is used for internal structures within a building, while muro refers to external barriers surrounding a piece of land.
Parede
A1This word usually refers to an interior wall that partitions rooms within a house, apartment, or building. It can also refer to the vertical inner surfaces of containers or biological organs.
Eu pendurei um quadro bonito na parede da sala.
(I hung a beautiful picture on the living room wall.)
As paredes deste quarto precisam de uma nova pintura.
(The walls of this bedroom need a new paint job.)
Eu encostei a escada na parede para trocar a lâmpada.
(I leaned the ladder against the wall to change the lightbulb.)
Os vizinhos reclamam porque as paredes são muito finas.
(The neighbors complain because the walls are very thin.)
O médico examinou a parede do estômago do paciente.
(The doctor examined the wall of the patient's stomach.)
Muro
A2This word refers to an exterior wall typically built of brick or stone to enclose a yard, garden, or property. It separates private land from the street or from neighbors.
O gato gosta de dormir em cima do muro do quintal.
(The cat likes to sleep on top of the backyard wall.)
Eles construíram um muro alto para ter mais privacidade.
(They built a high wall to have more privacy.)
O ladrão pulou o muro e entrou na propriedade.
(The thief jumped over the wall and entered the property.)
A bola de futebol caiu do outro lado do muro.
(The soccer ball fell on the other side of the wall.)
O Muro de Berlim caiu em 1989.
(The Berlin Wall fell in 1989.)
Summary
To choose the right word, simply look at where the wall is located. If it is inside a building dividing rooms, use parede. If it is outside marking the boundary of a property or garden, use muro.